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Tsilaisite (no replies)

Rock Currier — Fri, 14 Dec 2012 12:01:36 +0000

Click here to view Best Minerals and here for Tourmaline group minerals, here for Chromium-dravite, here for Chromo-alumino-povondraite, here for Dravite, here for Elbaite, Afghanistan to Nigeria, here for Elbaite, Pakistan to Zambia here for Feruvite, here for Fluor Buergerite here for Fluor-dravite, here for Fluor-elbaite, here for Fluor-feruvite, here for Fluor-liddicoatite, here for Fluor-schorl, here for Foitite, here for Liddicoatite, here for Luinaite-(OH), here for Magnesiofoitite, here for Olenite, here for Oxy-dravite, here for Oxy-rossmanite, here for Oxy-schorl, here for Povondraite, here for Rossmanite, here for Schorl, here for Tsilaisite and here for Vanadium-dravite. Click here for Best Minerals T and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Tailaisite : Trigonal: The OH analogue of fluor-tsilaisite.
Na(Mn²⁺)₃Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)


Tailaisite, FOV 1.3mm, Elba, Italy	© Yaiba Sakaguchi

The above image of a tsilaisite specimen is from Grotta d'Oggi Quarry, San Piero in Campo, Campo nell'Elba, Elba Island, Livorno Province, Tuscany, Italy

Mindat currently lists only two localities for tailaisite. The type locality for tailaisite is Grotta d'Oggi Quarry, San Piero in Campo, Campo nell'Elba, Elba Island, Livorno Province, Tuscany, Italy. Mindat has only one picture of a tailaisite specimen.

Click here to view Best Minerals and here for Tourmaline group minerals, here for Chromium-dravite, here for Chromo-alumino-povondraite, here for Dravite, here for Elbaite, Afghanistan to Nigeria, here for Elbaite, Pakistan to Zambia here for Feruvite, here for Fluor Buergerite here for Fluor-dravite, here for Fluor-elbaite, here for Fluor-feruvite, here for Fluor-liddicoatite, here for Fluor-schorl, here for Foitite, here for Liddicoatite, here for Luinaite-(OH), here for Magnesiofoitite, here for Olenite, here for Oxy-dravite, here for Oxy-rossmanite, here for Oxy-schorl, here for Povondraite, here for Rossmanite, here for Schorl, here for Tsilaisite and here for Vanadium-dravite. Click here for Best Minerals T and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

[The first draft of the Best Minerals article on tailaisite was finished in May 2013]

Titanite (20 replies)

Rudolf Hasler — Sat, 15 Dec 2012 09:42:11 +0000

Click here to view Best Minerals T, and here for Best Minerals A to Z and here for Fast Navigation for finished first draft Best Minerals articles.

Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Titanite
CaTi(SiO₄)O Monoclinic


Titanite from Graukogel 5 x 3,5cm	© Chr. Hager

Titanite also known as sphene (from Greek sphenos which means wedge-shaped), forms flattened wedge-shaped crystals, commonly twinned with prominent re-entry angles; massive, compact and lamellar forms are also found. It occurs as an accessory mineral in igneous rocks; in schists, gneisses and other metamorphic rocks, and is also found as a detrital mineral in some sedimentary deposits.
The type locality of Titanite is: Germany, Bavaria, Bavarian Forest, Passau, Graphite mines. It was discovered in 1795. Source localities include: Pakistan; Italy; Russia; China; Brazil; Tujetsch, St. Gothard, Switzerland; Madagascar; Salzburg, Austria; Renfrew County, Ontario, Canada; Sanford, Maine, Gouverneur, Diana, Rossie, Fine, Pitcairn, Brewster, New York and California in the USA.
Mindat currently lists 3806 localities where Titanite has been found.
The biggest crystals measuring 16cm have been found at Capelinha in Brazil.
As a gemstone it is very high prized for its exceptional dispersive power which is said to even exceed that of diamonds.

Titanite
Afghanistan
Afghanistan, Badakhshan Province (Badakshan Province; Badahsan Province), Jurm District, Koksha Valley (Kokscha Valley; Kokcha Valley), Jurm (Firghamu; Firgamu), Auraghuq


Titanite 2,4 x 1,3cm	© Rob Lavinsky

Titanite
Afghanistan
Afghanistan, Badakhshan Province (Badakshan Province; Badahsan Province), Khash & Kuran Wa Munjan Districts, Koksha Valley (Kokscha Valley; Kokcha Valley)[/b]


Titanite 2 x 1,3cm	© H. Obodda


Titanite 3,4 x 1,2cm	© Jose Zendrera

Titanite
Australia
Australia, New South Wales, Yancowinna Co., Huonville Station


Titanite xls 3,2cm & 2,1cm across	©

Approximately thirty kilometres south of Broken Hill, on the flank of a small rise, is a curiosity of sorts. On this hill is a pit that was worked periodically over the last seventy years as a source of gem quality sphene – the old alternative gemstone name for the mineral titanite.
The titanite occurs in a pipe style deposit that is suggested to have formed during retrograde metamorphism along fracture zones in the Little Broken Hill Gabbro. This gabbro is largest of several ultrabasic intrusives in the Broken Hill block post dating the high-grade metamorphic rocks that dominate in the region. The outcrop of the gabbro has a distinct red-brown colour and is clearly seen on aerial photographs contrasting darker against the surrounding metamorphic rocks.
_{Trevor Dart}

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Ankogel group, Ankogel area, Grauleitenspitze (south slope)


Titanite, Albite 1,5cm on an edge	©

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Ankogel group, Ankogel area, Arnoldhöhe


Titanite 0,9cm, Quartz	© Rudo

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Ankogel group, Dösenbach valley


Titanite, Quartz 7cm wide	© H. Prasnik

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Ankogel group, Mallnitz, Auernig


Titanite, Pericline xls up to 1cm	© Rudo


Titanite, Pericline xls up to 1,8cm	© Rudo


Titanite, Pericline 8cm wide	© Rudo


Titanite, Quartz 2,8cm	© Rudo


Titanite on Quartz xls up to 1,8cm	© G. Hörnler


Titanite 2,5cm	© G. Hörnler

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Ankogel group, Seebach valley


Titanite on Quartz 13,5cm wide	© G. Hörnler


Titanite, Quartz 8cm high	© G. Hörnler


Titanite 6cm on an edge	© G. Hörnler


Titanite xls up to 4cm	© Rudo

In 1997 it was Gerhard Hörnler to open the best Carinthian Titanite cleft in Seebach valley not far away of the road. The quartz vein had been inspected by lots of 'Stansuacha' (Carinthian expression for people collecting alpine minerals) including the author of these lines. Nobody had expected that this long vein (over 10 meters) would reveal such a treasure. Funnily enough the pocket was right under the place where many of us had been sitting and having our lunch when working at this locality.
It took Gerhard only about a quarter of an hour to break through the quartz vein. Together with his friend Axel Krappinger he rescued Titanite crystals in outstanding size and quality. The biggest crystal is measuring 6cm on an edge. Sometimes Rock Crystals are the matrix for grass green Titanites.

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Ankogel group, Seebach valley, Törlkopf - Törlspitz area


Titanite 4 x 3cm	© Rudo


Titanite 3,5cm wide	© Rudo


Titanite xls up to 1cm	© M. Döpper


Titanite xls up to 1cm	© M. Döpper


Titanite, Pericline 15cm wide	© H. Fink

Although Titanite crystals (Sphene) can be found at lots of localities in the Eastern Alps, good or excellent specimens are rather rare and are concentrated on only a few mountains. One of these is the Ankogel group in Carinthia. Alpine clefts in Amphibolite schists have produced beautiful crystals in yellow, brown, and most desirable green color which sometimes are decoratively placed on white Albite.

Titanite
Austria
Austria, Carinthia, Hohe Tauern, Reißeck group, Kolbnitz, Riekengraben, Moos Alp (Untere Mooshütte - Obere Mooshütte area)


Titanite, Stilbite 1,6cm	©


Titanite xls up to 1,4cm	©

Titanite
Austria
Austria, Tyrol, East Tyrol, Kals valley, Dorf valley, Laperwitzgraben


Titanite, Albite 14cm wide	©


Titanite 3,7cm	© Martin Gruell


Titanite 5,5 x 3cm	© H. Fink

In 1968 Austria's cleft of the century containing unbelievable amounts of dark green Sphenes (Titanites) in sizes up to 8cm was discovered in Laperwitzgraben near Kals by the policeman Kurt Tscharitsch and the tailor Sepp Walder. As both were very unexperienced prospectors they were not at all aware what they had found. They carelessly threw Scheelites weighing more than 3 kg and Milarite crystals measuring 2cm on the dump. By showing off with their crystals in pubs they caused a run to the cleft that almost reminded to a gold rush. Several groups were working the cleft then, some even using dynamite. Most of the precious minerals were damaged or broken. Buckets were filled with loose Titanite crystals in very best quality but undamaged specimens with Sphenes on matrix remained an exception.

Titanite
Austria
Austria, Tyrol, East Tyrol, Kals valley, Teischnitz valley, Gramul


Titanite, Calcite 8 x 8cm	© Gerd Stefanik


Titanite on Calcite xtl size 2,4cm	© G. Hörnler

Titanite
Austria
Austria, Tyrol, East Tyrol, Virgen valley, Prägraten, Timmelbach valley, Gastacherwände


Titanite, Albite 3,5cm wide	© Rudo


Titanite xtl size 1,6mm	© Chinellato Matteo


Titanite, Calcite 6cm wide	© Rudo

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Untersulzbach valley, Käferfeld glacier - Schwarzes Hörndl area


Titanite xls up to 3,5cm	© H. Fink


Titanite FOV: 1,8cm	© 2005 M. Kampf

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Habach valley, Teufelsmühle


Titanite FOV: 0,6cm	© Harjo


Titanite 5,2cm	© Anton Watzl Sr.


Titanite xls up to 2,5cm	© H. Fink

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Habach valley, Graukogel


Titanite & Adularia xls up to 4cm	© Chr. Hager


Titanite 6cm wide	© Chr. Hager


Titanite 4cm	© Chr. Hager


Titanite 16 x 9cm	© Chr. Hager


Titanite 4cm	© Chr. Hager


Titanite on Adularia 8cm wide	© Chr. Hager


Titanite, Adularia 5 x 3,5cm	© Chr. Hager

Heinz Kirchtag and Andreas Steiner were on their way to the Lienzinger mountain in Hollersbach valley. They had started from the Habach valley. Near the top of Graukogel mountain they inspected some quarz veins although they did not really expect to find something nice there. But what they found were probably the best Titanites of the Alps in the most beautiful dark green color. The biggest one measures incredible 13cm.

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Habach valley, Gamsmutter, East slope


Titanite xls up to 2,4cm	© www.mineralienkluft.at


Titanite xls up to 1cm	© Martin Gruell

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Hollersbach valley, Bruchgraben


Titanite 9,5cm high	© Gerd Stefanik


Titanite, Albite xls up to 1,3cm	© Chr. Hager

The Bruchgraben, a small eastern side valley of the Hollersbach valley, branches roughly opposite to the Scharnbachgraben. Clefts in rocks of the Habach formation in the upper valley yielded well crystallized specimens with very large crystals of scheelite, titanite, calcite and rock crystal.
The Titanite crystals found in Bruchgraben are in most cases of outstanding gem quality.

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Hollersbach valley, Senning gorge (Speibing gorge)


Titanite 3,5cm high	© Chr. Hager


Titanite 3,5cm high	© Chr. Hager

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Felben valley


Titanite 5 x 3,7cm	© Conny Larsson


Titanite, Adularia 2,5cm high	© Rudo

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Felben valley, Amerbach valley, Wag Alp


Inside a great Titanite cleft	© A. Steiner


Titanite 15,5 x 8,5cm	© Wegener


Titanite 5cm high	© Wegener


Titanite 5,2cm high	© Wegener


Titanite on Quartz 8cm	© Wegener


Titanite crystal size 4,6cm	© Wegener


"Mr. Titanite" Andi Steiner at his cleft on Wag Alp	© Wegener

In 2011 Andi Steiner discovered a great Titanite cleft on Wag Alp at a place where avalanches had exposed amphibolite rocks. To rescue the wonderful Titanites in best quality and green color he washed away the tough pressed Chlorite by using the water of a nearby brook.This careful technique had also been successfully used by his father when finding Titanite clefts.

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Felben valley, Schiedergraben


Titanite, Actinolite FOV: 1cm	© mk


Titanite FOV: 0,6cm	© Harjo


Titanite FOV: 0,8cm	© Chinellato Matteo


Titanite 0,6cm	© Harjo


Titanite 15 x 8cm	© www.mineralienkluft.at

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Stubach valley, Ödenwinkel area, Eiskögele (north face)


Titanite 4,5 x 3,5cm	© Chr. Hager


Titanite on Albite 10cm high	© Chr. Hager


Titanite, Albite 3,5 x 3cm	© Chr. Hager

In the Eiskögele north face the Hofer brothers, Hannes and Gerhard, found the three wonderful specimens displayed above like a heavenly gift lying on a little rock platform. They were the only rest of cleft which must have fallen down on the glacier. It is not hard to imagine what kind of material there must have been ruined.

Titanite
Austria
Austria, Salzburg, Hohe Tauern, Gastein valley, Anlauf valley, Knallkar


Titanite, Rock Crystal, Clinochlore 7 x 7,5cm	©

Titanite
Austria
Austria, Styria, Koralpe, Deutschlandsberg, Warnblick, Schwemmhoisl farm, Amphibolite quarry (Schwemmhoisl quarry)


Titanite on Albite 7 x 4cm	©


Titanite 17cm high	© H.P.Bojar


Titanite 15cm wide	© H.P.Bojar


Titanite 5 x 4,5cm	© H. Fink

In the 1970's some remarkable alpine clefts were opened in the amphibolite quarry that contained huge Rock Crystals, Albites, and Titanites measuring up to 10cm.

Titanite
Belgium
Belgium, Luxembourg Province, Bastogne, Sur les Roches Quarry


Titanite 3 x 2,4cm	© JDehove


Titanite, Chamosite FOV: 1cm	© Harjo


Titanite, Anatase FOV: 0,6cm	© Harjo

Titanite
Brazil
Brazil, Minas Gerais, Jequitinhonha Valley, Capelinha


xtl 3,2cm	© Dan & Diana Weinrich Minerals


Titanite xls up to 2,7cm	© Bráulio


Titanite 7,5cm	© Dan & Diana Weinrich Minerals


Titanite 3,8 x 2,7cm	© Henry Minot 2010


Titanite xtl 1,8cm	© Rob Lavinsky


Titanite 3,5 x 2,9cm	© Rob Lavinsky


Titanite 3,5 x 2,3cm	© Collectors Edge


Titanite, Epidote 7cm high	© Rudo

Alpine-type clefts. Titanites in sizes up to 16cm. The area around Capelinha is one of the world's best Titanite occurrences.

Titanite
Brazil
Brazil, Minas Gerais, Jequitinhonha Valley, Capelinha, Campo do Boa Mine


Titanite 9,3 x 5,8cm	© Rob Lavinsky


Titanite 6,3 x 6cm	© Rob Lavinsky


Titanite 7,3 x 5,1cm	© Antonio Borrelli


Titanite, Albite xls up to 3cm	© LAZZARI FRANCO


Titanite FOV: 2,5cm	©

Titanite
Brazil
Brazil, Minas Gerais, Jequitinhonha Valley, Capelinha, Fazenda Rubin Pimenta Mine


Titanite 13,6cm high	© Rob Lavinsky


Titanite, Quartz 8,1 x 5,5cm	© Rob Lavinsky

Titanite
Canada
Canada, Ontario, Haliburton Co., Cardiff Township, Cardiff Uranium Mine


Titanite 3,5 x 3cm	©


Titanite 2,3 x 2cm	© Maggie Wilson

In veins cutting amphibolite & syenite gneiss; crystalline limestone.
The deposit was originally explored for fluorite in 1943 by Cardiff Fluorite Mines Limited: exploration for uranium was conducted by Cardiff Uranium Mines Limited from 1953 to 1955. The mineralization extends for about 3 kilometers along the contact of geniss and crystalline limestone. The development at the South Zone consists of two adits, a shaft to a depth of 83.8 meters, and trenches. The openings are on the eastern slope of a ridge overlooking Irondale River.

Titanite
Canada
Canada, Ontario, Haliburton Co., Cardiff Township, Clark Mine (Ball mine; Topspar mine)


Titanite 2,1cm	© M.Adamowicz


Titanite 5,6 x 4,3cm	©

In syenite pegmatite intruding hornblende gneiss.
"The deposit was worked for fluorite by Mr. W.E Clark from 1940 to 1942; shipments totalling 27.2 t of acid-grade fluorite were made. The ore was obtained from several pits and trenches extending over a distance of 180 m along the top of a hill. In 1950 Topspar Fluorite Mines, Limited conducted exploration consisting of an open-cut (3 m by 24 m) and an adit driven 27 m from the south end of the cut on the north side of the hill. A mill was conducted on the site."

Titanite
Canada
Canada, Ontario, Haliburton Co., Monmouth Township, Gooderham, Bear Lake diggings (Gibson Road Western occurrence)


Titanite, Scapolite 2,5 x 2cm	© 2001 John H. Betts


Titanite 2,8 x 2cm	© 2001 John H. Betts


Titanite 4cm high	© D.K.Joyce


Titanite 5,3cm	© CCURTO2010


Titanite, Microcline Titanite 22cm across	© David K. Joyce

Titanite
Canada
Canada, Ontario, Haliburton Co., Monmouth Township, Tory Hill, Millar's Mine


Titanite 2,5cm across	©

In calcite veins cutting graphic granite pegmatite.
Was opened around 1900 as a radioactive mineral and phosphate prospect and consists of two open-cuts, two trenches, and an adit (9 m long).

Titanite
Canada
Canada, Ontario, Renfrew Co., Bonnechere Valley Township (formerly the Village of Eganville and the former Townships of Grattan; Sebastopol and South Algona), Eganville


Titanite 5cm wide	©


Titanite 3,9 x 2,7cm	© Rob Lavinsky

Titanite
Canada
Canada, Québec, Montérégie, Rouville RCM, Mont Saint-Hilaire, Poudrette quarry (Demix quarry; Uni-Mix quarry; Desourdy quarry; Carrière Mont Saint-Hilaire)


Titanite FOV: 0,4cm	© Stephan Wolfsried


Titanite FOV: 0,4cm	© Stephan Wolfsried

Titanite
Canada
Canada, Québec, Outaouais, Pontiac RCM, Litchfield, Bear Lake


Titanite 2,8 x 2,2cm	© 2002 John H. Betts


Titanite 10cm wide	©

Titanite
Czech Republic
Czech Republic, Moravia (Mähren; Maehren), Olomouc Region, Jeseník, Žulová (Friedeberg), Boží Hill (Gotteshausberg)


Titanite xtl size: 0,6cm	© Filip Kopecky


Titanite xtl size: 0,5cm	© A.Tomek

Abandoned quarries and diggings at contacts between Zulová massif granitoids and Ca-marbles.

Titanite
Czech Republic
Czech Republic, Moravia (Mähren; Maehren), Olomouc Region, Šumperk (Mährisch Schönberg), Krásné


Titanite xls up to 0,4cm	© fabreminerals.com

Titanite
France
France, Provence-Alpes-Côte d'Azur, Hautes-Alpes, Briançon


Titanite xtl size: 2,02mm	© Chinellato Matteo


Titanite 1,81mm, Quartz	© Chinellato Matteo


Titanite xtl size: 1,52mm	© Chinellato Matteo

Titanite
Germany
Germany, Bavaria, Lower Bavaria, Bavarian Forest, Hauzenberg, Titanite occurrence


Titanite "type specimen" 9 x 6cm	© Humboldt-Universität, Berlin

Titanite
Germany
Germany, Rhineland-Palatinate, Eifel, Laach lake volcanic complex


Titanite FOV: 5mm	© Stephan Wolfsried


Titanite FOV: 5mm	© Stephan Wolfsried


Titanite FOV: 8mm	© Stephan Wolfsried


Titanite FOV: 3mm	© Stephan Wolfsried


Titanite FOV: 3mm	© Stephan Wolfsried


Titanite FOV: 3mm	© Stephan Wolfsried

Titanite
Germany
Germany, Rhineland-Palatinate, Eifel, Laach lake volcanic complex, Mendig, Niedermendig, In den Dellen quarries


Titanite FOV: 2,5mm	© Fred Kruijen


Titanite FOV: 4mm	© Elmar Lackner


Titanite FOV: 2,3mm	© Elmar Lackner 2009


Titanite xtl size: 2,15mm	© Chinellato Matteo

Titanite
Germany
Germany, Rhineland-Palatinate, Eifel, Mayen, Ettringen, Bellerberg volcano, Caspar quarry


Titanite FOV: 4mm	© Stephan Wolfsried


Titanite FOV: 5mm	© Stephan Wolfsried

Titanite
Italy
Italy, Campania, Naples Province, Somma-Vesuvius Complex, Monte Somma


Titanite xtl size: 1,78mm	© Chinellato Matteo


Titanite 2,93mm	© Chinellato Matteo

Titanite
Italy
Italy, Aosta Valley, Châtillon, Bellecombe


Titanite xtl 1,2cm	© Chinellato Matteo

Titanite
Italy
Italy, Aosta Valley, Courmayeur, Monte Bianco Massif (Mont Blanc Massif), Veny Valley, Miage Glacier


Titanite xtl 4mm	©


Titanite 6 x 3,3cm	©

Titanite
Italy
Italy, Aosta Valley, Courmayeur, Monte Bianco Massif (Mont Blanc Massif), Veny Valley, Punta Helbronner


Titanite xtl 3,5mm	© Fontana Gianluca

Titanite
Italy
Italy, Aosta Valley, Saint-Marcel, Prabornaz Mine (ex Praborna Mine)


Titanite (Var. Greenovite) xtl 1cm	© GiovanniFraccaro

Titanite
Italy
Italy, Emilia-Romagna, Parma Province, Varsi, Ceno Valley, Rocca Predellara quarry (Tosca quarry)


Titanite xtl 1,79mm	© D. Preite - M.C.

Titanite
Italy
Italy, Latium, Rome Province, Tolfa Mts District, Allumiere, Monte Sassetto


Titanite xtl 1mm	© Di Domenico Dario

Titanite
Italy
Italy, Latium, Rome Province, Tolfa Mts District, Allumiere, Spizzicatore Hill


Titanite 3 x 2mm	© Di Domenico Dario

Titanite
Italy
Italy, Latium, Viterbo Province, Làtera volcano, Onano, Montenero quarry


Titanite on Hauyne xtl 2mm	© Chinellato Matteo


Titanite FOV 3mm	© Stephan Wolfsried


Titanite xtl 1,51mm	© D. Preite - M.C.


Titanite xtl 1,74mm	© Chinellato Matteo


Titanite FOV 3,3mm	© Yaiba Sakaguchi

Titanite
Italy
Italy, Piedmont, Torino Province, Sesia-Lanzo zone, Lanzo Valley, Viù Valley, Usseglio, Margone


Titanite 7,25mm	© Chinellato Matteo

Titanite
Italy
Italy, Piedmont, Verbano-Cusio-Ossola Province, Formazza Valley, Formazza


Titanite, Anatase xtl 1,59mm	© Chinellato Matteo

Titanite
Italy
Italy, Piedmont, Verbano-Cusio-Ossola Province, Formazza Valley, Formazza, Forno glacier


Titanite xtl 7mm	© Chinellato Matteo

Titanite
Italy
Italy, Piedmont, Verbano-Cusio-Ossola Province, Ossola Valley, Beura-Cardezza, Beura Quarries


Titanite xtl 2,59mm	© D. Preite - M.C.


Titanite xtl 1,51mm	© D. Preite - M.C.


Titanite xtl 1,14mm	© Chinellato Matteo

Titanite
Italy
Italy, Trentino-Alto Adige, Bolzano Province (South Tyrol), Aurina Valley (Ahrnbach Valley)


Titanite xtl 1,2cm	© Chinellato Matteo


5,07mm	© Chinellato Matteo


Titanite 3,6 x 2,2cm	© Simone Citon

Titanite
Italy
Italy, Trentino-Alto Adige, Bolzano Province (South Tyrol), Aurina Valley (Ahrnbach Valley), Vento Valley (Wind Valley)


Titanite xtl 1,8cm	© Chinellato Matteo

Titanite
Italy
Italy, Trentino-Alto Adige, Bolzano Province (South Tyrol), Pusteria Valley (Puster Valley), Vandoies, Fundres Valley


Titanite xtl 7,5mm	© Chinellato Matteo

Titanite
Italy
Italy, Trentino-Alto Adige, Bolzano Province (South Tyrol), Pusteria Valley (Puster Valley), Vandoies, Fundres Valley, Cora Mt. (Gschirn)


Titanite xtl 1,2cm	© Chinellato Matteo


Titanite xtl 1,2cm	© Chinellato Matteo

Titanite
Madagascar
Madagascar, Antsiranana Province, Sava (Northeastern) Region, Vohémar District, Ankarafa


Titanite 5,1 x 2,7cm	© Rob Lavinsky


Titanite 6,5 x 5cm	© Rob Lavinsky


Titanite 3,2 x 1,8cm	© www.quebulfineminerals.com

Titanite
Madagascar
Madagascar, Fianarantsoa Province, Vatovavy-Fitovinany Region, Mananjary District, Mananjary emerald District, South Zone, Morafeno


Titanite 3 x 2cm	© Arliguie M

Titanite
Morocco
Morocco, Meknès-Tafilalet Region, Er Rachidia Province, Imilchil


Titanite 3 x 2,8cm	© fabreminerals.com


Titanite, Orthoclase 4,3 x 3,8cm	© fabreminerals.com


Titanite xtl 1,3cm	© fabreminerals.com


Titanite 5,8cm wide	© www.spiriferminerals.com

Titanite
Namibia
Namibia, Khomas Region, Gamsberg Area


Titanite 5 x 2,8cm	© Rob Lavinsky


Titanite 5,1 x 2,4cm	© E.A. Schnaitmann

The Gamsberg Mt. is a 2.437 m high granite peak in the Khomas Region, it's the third highest mountain of Namibia.
The area is known for Alpine-type cleft minerals. Strictly speaking, the localities are in the Gamsberg foreland (outland).
The Gamsberg Area refers to a loosely-defined area roughly 70 by 70 kilometers from east to south. The area is east of the Gamsberg and Hakos Mountains, located in the southwestern part of central Namibia.
The Gamsberg Mountain is the most important landmark in the area, but no known alpine-type fissures or minerals have been found on the actual mountain. The position of specific finds is difficult to find details on, due to the erratic distribution of the fissures as well as the fact that the whole area is subdivided into privately owned farmland.
In general, the farmers are extremely reluctant to allow anyone, including local prospectors, onto their properties. Therefore, some local miners have taken to moonlighting when the farmers are away on other business, and will not divulge any specific localities to mineral collectors for fear of reprisal.
However, collectors are seriously warned not to attempt to enter any of these farms without explicit prior consent from the farm owners.

Titanite
Norway
Norway, Nordland, Fauske, Sulitjelma, Stokkviknakken Tunnel


Titanite 2,2cm wide	© OT. Ljostad

A road tunnel along the road "Fylkesvei 830", between Finneid and Sulitjelma in the municipality of Fauske. The road is laid on the old railway tracks of the now closed Sulitjelma Railroad. More than 100 specimens of collector-quality titanite specimens were found here in 1991. Specimens from this find were often labelled just "Fauske" or "Sulitjelma".

Titanite
Pakistan
Pakistan, Balochistan (Baluchistan)


Titanite 2,2 x 1,7cm	©

Titanite
Pakistan
Pakistan, Federally Administered Tribal Areas (FATA), Khyber Agency, Mulla Ghori


Titanite 4,4 x 4,2cm	© Rob Lavinsky


Titanite xtl 3,5cm	© 2009 Jesse Fisher


Titanite 2,2 x 2,2cm	© TVM


Titanite 9,4 x 6cm	© Rob Lavinsky


Titanite 3,5cm	© C. Stefano '12

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan


Titanite, Diopside 3 x 1,8cm	© Michael C. Roarke

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu district, Basha Valley (Basha Nala; Basna), Arondu (Arundu; Arandu)


Titanite, Adularia 3 x 2,1cm	© Rob Lavinsky


Titanite 3,5 x 2,1cm	© www.quebulfineminerals.com

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu District, Haramosh Mts.


Titanite xtl 2,9cm	© 1995-2001 Trinity Mineral Co.


Titanite xtl 1,8cm	© Rudo


Titanite 6,4 x 5cm	© Rob Lavinsky


Titanite 7 x 4,4cm	© fabreminerals.com


Titanite 4,4 x 3,5cm	© fabreminerals.com


Titanite, Albite 5,5 x 4,2cm	© Lopatkin Oleg

Mountain range north of the Indus River between Gilgit and Skardu, hosting numerous complex granitic pegmatite fields and alpine cleft-type metamorphic deposits. Mountain range crossed the border between the Skardu and Gilgit Districts.

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu District, Haramosh Mts., Tormiq valley (Tormic; Tormik; Tormig; Turmiq)


Titanite, Adularia 2,1 x 2cm	© Rob Lavinsky


Titanite xls up to 1,8cm	© Carles Millan


Titanite xtl 1,2cm	© Rob Lavinsky


3,7 x 3,5cm	© Dan & Diana Weinrich Minerals


2,9cm	© Weinrich Minerals, Inc.


Titanite 5,1 x 3,3cm	© www.quebulfineminerals.com


Titanite, Calcite 2,1 x 1,6cm	© www.quebulfineminerals.com

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu District, Shigar Valley


Titanite 3 x 2cm	© Rob Lavinsky


Titanite, Schörl 4,9 x 4,7cm	© Carles Millan

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu District, Shigar Valley, Hachupa (Hashupi)


Titanite, Albite 10 x 7cm	© Weinrich Minerals, Inc.

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Baltistan, Skardu District, Shigar Valley, Hachupa (Hashupi), Hachupa Epidote Locality


Titanite, Epidote 3cm wide	©

A village in the Shigar River Valley, between Alchuri and Shigar. Alpine cleft-type metamorphoc deposits in the area.

Titanite
Pakistan
Pakistan, Gilgit-Baltistan (Northern Areas), Diamar District (Diamir District), Tangir Valley


Titanite 3 x 1,3cm	© TVM

Titanite
Portugal
Portugal, Leiria District, Leiria, Monte Redondo, Montijos Quarry


Titanite FOV: 14mm	© 2005 M. Kampf


Titanite xtl 5mm	© Rui Nunes 2013

Gabbro quarry.
In the area known as "Montijos Quarry" there were 3 distinct mining concessions
1 - "Quinta dos Montijos" concession nr 1102, operated by Pedreiras de Monte Redondo, Lda, closed on August 17, 1966.
2 - "Montijos Nr 1" concession nr 1323, operated by Domingos Pereira Amado and Others, closed on January 24, 1972.
3 - "Cabeço da Quinta" concession nr 917, operated by Sociedade de Paralelepípedos do Sul, Lda, closed on May 31, 1973.

Titanite
Russia
Russia, Urals Region, Middle Urals, Ekaterinburgskaya (Sverdlovskaya) Oblast'


Titanite xtl size: 7mm	© B.Z. Kantor

Titanite
Russia
Russia, Urals Region, Middle Urals, Permskaya Oblast', Gornozavodskii area, Saranovskaya (Sarany) Village, Saranovskii Mine (Saranovskoe)


Titanite 3,2 x 1,5cm	© Dan Weinrich


Titanite 3,5 x 2,5cm	© Oleg Lopatkin

Titanite
Russia
Russia, Urals Region, Southern Urals, Chelyabinsk Oblast', Zlatoust, Nazyamskie Mts, Akhmatovskaya Kop' (Achmatovsk Mine)


Titanite FOV: 5 x 3,5cm	© Sergei Kolisnichenko

Titanite
Russia
Russia, Western-Siberian Region, Polar Urals, Tyumenskaya Oblast', Neroyka Mt


Titanite 6,6 x 4,1cm	© Weinrich Minerals, Inc.

Titanite
Russia
Russia, Western-Siberian Region, Prepolar Ural, Tyumenskaya Oblast', Khanty-Mansi (Khanty Mansiysk) Okrug, Saranpaul, Dodo Mine


Titanite 5,5 x 3,5cm	© CCURTO2010


Titanite 4,7 x 3,6cm	© Rob Lavinsky

Titanite
Russia
Russia, Western-Siberian Region, Prepolar Ural, Tyumenskaya Oblast', Khanty-Mansi (Khanty Mansiysk) Okrug, Saranpaul, Puiva (Pouyva) Mount


Titanite xtl 1,1cm	© SMS 2008

Titanite
Spain
Spain, Andalusia, Granada, Monachil, Pradollano


Titanite FOV 4mm	© Antonio Pliego

Titanite
Switzerland
Switzerland, Grischun (Grisons; Graubünden), Vorderrhein Valley, Tujetsch (Tavetsch), Curnera Valley


Titanite xtl 1cm

Titanite
Switzerland
Switzerland, Grischun (Grisons; Graubünden), Vorderrhein Valley, Tujetsch (Tavetsch), Sedrun, Druntobel (Drun Tobel; Drun Sedrun; Krüzli valley; Kreuzli pass; Ruinas Plaunas)


Titanite 10cm high	©

Titanite
Switzerland
Switzerland, Ticino (Tessin), Maggia Valley, Lavizzara Valley, Mogno, Arena Alp


Titanite 6,5mm wide	© Chinellato Matteo


Titanite xtl 2,82mm	© Chinellato Matteo

Titanite
Switzerland
Switzerland, Wallis (Valais), Goms, Fiesch, Wannenhorn


Titanite xtl 2,07mm	© Chinellato Matteo

Titanite
Switzerland
Switzerland, Wallis (Valais), Zermatt - Saas Fee area, Saas Valley, Saas Fee


Titanite 2,4mm wide	© 2007 D. Schläfli

Titanite
Tanzania
Tanzania, Arusha Region, Lelatema Mts, Merelani Hills (Mererani), D-Block Mine


Titanite 2,1 x 1cm	© Marin Mineral

D-Block Mine is a gem (Tanzanite) mine worked by only a small group of miners.

Titanite
Tanzania
Tanzania, Morogoro Region, Mahenge


Titanite 3,7 x 3,2cm	© Oleg Lopatkin

Titanite
USA
USA, Maine, York Co., Sanford, Webster prospects (Sanford vesuvianite locality; Goodall Farm prospect; Webster vesuvianite prospect)


Titanite xtl 1,4cm	© 2007 Peter Cristofono

Profesor John W. Webster of Harvard University operated this quarry for specimens and described vesuvianite from this locality in an article in American Journal of Science in 1848. It was later worked by Mr. Goodall of Sanford whose family owned a famous mill in the town and where there was once a private natural history museum.

Titanite
USA
USA, Massachusetts, Bristol Co., Acushnet, Acushnet Quarry (P. J. Keating Quarry; Tilcon Capaldi Quarry; Warren Brothers Quarry; Blue Stone Quarry; Old Bluestone Quarry)


Titanite xtl 5mm	© 2008 Peter Cristofono

Crushed stone quarry originally operated by the Blue Stone Quarry Co.

Titanite
USA
USA, Montana, Jefferson Co., Boulder Batholith


Titanite 2,5 x 1,5cm	© Wm. C. van Laer


Titanite 1,7 x 1,4cm	© Rob Lavinsky

Titanite
USA
USA, New Hampshire, Hillsborough Co., Amherst, Joppa Hill


Titanite, Grossular xtl 4mm	© 2008 Peter Cristofono

The Joppa Hill prospects are in Amherst, close to the Amherst-Bedford line. A vesuvianite crystal from this locality was illustrated in the 2nd edition of Dana's System of Mineralogy (1844). Mineralization occurs in bedrock exposures of contact metamorphosed limestone and in a quartz vein, both in Amherst. Boulders extending across the town line into Bedford also produce specimens. This mineral list includes occurrences in both towns.

The locality was first discovered by a Dr. Spaulding of Amherst who noticed some unusual rocks in stone walls of the area. The source of these stones was discovered in a ravine on the land of Betsey Stevens. Dr. Spaulding (and a Mr. Peabody) guided geologist Charles Jackson to the locality. Jackson described the rock as being exactly like the "limestone" of Phippsburg, Maine. (Jackson, 1844)

Titanite
USA
USA, New Jersey, Bergen Co., Fort Lee, Interstate 95 and George Washington Bridge Lower Level roadcut


Titanite, Apatite FOV 5,4mm	© Saul Krotki 2005


Titanite, Apatite FOV 4,8mm	© Saul Krotki 2005

This locality was a massive, deep roadcut into the Palisades diabase cliffs to accomodate the interstate highways and the lower level installation of the George Washington bridge. The excavations encountered some coarsely crystallized and vuggy areas of the diabase.

Rudolf Hasler 12/13/2012

Click here to view Best Minerals T and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Tourmaline group (4 replies)

Rock Currier — Thu, 03 May 2012 21:37:30 +0000


©

Click here to view Best Minerals and here for Tourmaline group minerals, here for Chromium-dravite, here for Darellhenryite, here for Chromo-alumino-povondraite, here for Dravite, here for Elbaite, Afghanistan to Nigeria, here for Elbaite, Pakistan to Zambia here for Feruvite, here for Fluor Buergerite here for Fluor-dravite, here for Fluor-elbaite, here for Fluor-feruvite, here for Fluor-liddicoatite, here for Fluor-schorl, here for Foitite, here for Liddicoatite, here for Luinaite-(OH), here for Magnesiofoitite, here for Olenite, here for Oxy-dravite, here for Oxy-rossmanite, here for Oxy-schorl, here for Povondraite, here for Rossmanite, here for Schorl, here for Tsilaisite and here for Vanadium-dravite. Click here for Best Minerals T and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Tourmaline Group
Tourmaline is perhaps the main repository for boron in the earth's crust. Its stability field ranges from nearly standard temperature pressure condition (the weather outside) to 800 C and 60 kbar. It has a complex structure where many elements can enter into its composition and because of this the study of these elements and their location in the structure of the tourmaline species they can open a window on the conditions under which the tourmaline was formed and rocks that contain them. An issue in the Canadian Mineralogist in 2011 says that the study off tourmaline shows "that we are standing on the brink of a major breakthrough in the use of tourmaline as a quantitative indicator of the chemical and physical properties of its host environment these properties may well make tourmaline the prime mineral for this purpose." Tourmalines are found in many geological settings. Pegmatites produce many of the specimens cherished by collectors, many of which are pictured here, but they are also commonly found in granites and in metamorphic rocks like schist, shale, marble, conglomerate, dolostone and limestone. Because of their stability they are also found in sedimentary and meta sedimentary rocks. Under diagenetic conditions, tourmaline can develop as overgrowths on detrital tourmaline cores or as new, authigenic crystals.

Of all the different tourmaline species, black tourmaline (schorl) is by far the most abundant and may account for 90% or more of the earth's tourmaline. Schorl tourmaline has the longest history and can trace its description back to a German locality in 1400 and various tin mines in the Erzgebirge. Some are found abundantly in mica schist and some localities can produce thousands of well formed schorl crystals, sometimes of considerable size. They are also found in the cap rock of salt domes as are the povondraite specimens from Bolivia pictured below. At the tin Kami tin mine in Bolivia there are thousands, perhaps millions of tourmaline rich rock associated with the tin veins there. It was so abundant that during the second world war the Japanese, who had great difficulty getting borates, set up a refinery to recover boron from the rocks there. Tourmalines are even found in environments like magnesite deposits, like the one at Brumado in Minas Gerais state, Brazil where they are commonly found as uvite.

Below are listed the current members of the Tourmaline group of minerals. There are two philosophies about naming minerals. One we will call the splitters and the other the lumpers. The splitters want to give a new mineral name to every slight variation of composition and structure. Opposing them are the lumpers who would do away with many of the current mineral names. The lumpers might be personified by the late Dr. Fred Pough, one time curator of the mineral collection at the American Museum of Natural History. On more than one occasion I heard him say approximately this: "Whats the matter with Tourmaline? Tourmaline is a perfectly good name, you don't need all of these varieties to have their own name." Every mineral person worth their salt has their own opinion about what should be done about this mess and, at times, even the IMA at times vacillates back and fourth on the subject. One can't but feel sympathy with the lumpers when confronted with tourmaline crystals like the two immediately below. Each has three different tourmaline species in its structure. Many collectors would like to use one name to name but also feel uncomfortable calling them tourmaline because of the research in recent years has shown clearly that tourmaline is really a group name and not an individual species. If you don't know which tourmaline mineral(s) are represented in your crystal, just call it tourmaline or tourmaline group. However the considerable implications of the composition of various kinds of tourmalines in relationship to what they can tell us about the conditions that formed them and the rocks that host them almost demand that we be more precise about what we call various kinds of tourmalines.


Olenite/elbaite & schorl 4.3cm, Burma	© Lavinsky


Foitite/rossmanite/elbaite 2.2cm Elba, Italy	© Kohorst

Of all of the many specimens of tourmaline shown below and the links to many others, only a very few crystals of tourmaline have been adequately characterized to determine which tourmaline group mineral(s) they are. In the case of the pink mushroom from Burma above perhaps only two have been characterized. It was found that the predominate tourmaline species near its tip was olenite that graded into elbaite and then into black schorl at its base. It may be that all similar crystals have this same arrangement of tourmaline species in them, but drawing a firm conclusion about them based on such a small sample size is a risky business. Many of the tourmalines shown in this article will never be analysed because to do so would require that they be cut up to gain access to their interiors. The same is true of the crystals from Elba which may contain rossmanite.
Andreas Ertl, John M. Hughes, Stefan Prowatke, Thomas Ludwig, Franz Brandstätter, Wilfried Körner, and M. Darby Dyar (2007) TETRAHEDRALLY COORDINATED BORON IN Li-BEARING OLENITE FROM MUSHROOM TOURMALINE FROM MOMEIK, MYANMAR.

There are certainly tourmalines from other localities that have multiple tourmaline species in their structure, but the number of tourmaline crystals that have been accurately characterized is a vanishingly small as a percentage of all tourmalines. Also it is not a simple thing to correctly analyse a tourmaline, you can't just look at the color and know what it is. So when you are looking at tourmalines that have been given specific tourmaline group names, it has been done so on the basis of very few analysis of crystals from any particular locality and in most cases is just a best guess on the part of the collector, curator or mineral dealer. Many pegmatites are rich in fluorine for instance, and in those pegmatites one could expect that some if not all of the tourmalines found at that locality may be the fluor variety. Zoning in tourmalines is common, not only from top to bottom, but from the core of tourmalines outward. Some of this zoning is obvious in transparent and translucent tourmaline crystals and is in fact one of the main reasons why collectors are attracted to them. The more vivid the color change and the more colors a tourmaline crystal has, the more desirable it is to collectors. Studies have shown, that opaque tourmalines, commonly the black and brown ones also can have significant compositional zoning.

Tourmalines are found in many geological settings. Pegmatites produce many of the specimens cherished by collectors, but they are also found in metamorphic environments. Some are found abundantly in mica schist and these localities can produce thousands of well formed crystals, sometimes of considerable size. At the tin Kami tin mine in Bolivia there are thousands, perhaps millions of tourmaline rich rock associated with the tin veins there. It was so abundant that during the second world war the Japanese, who had great difficulty getting borates, set up a refinery to recover boron from the rocks there. It would have been very unpleasant to work in that factory I think. Tourmalines are even found in environments like magnesite deposits, like the one at Brumado in Minas Gerais state, Brazil where they are commonly found as uvites.

Each of the tourmaline group names listed below is linked first to its species page on Mindat and then to an individual Best Minerals article that tells more about each species and in some cases shows many more pictures of that particular kind of tourmaline. To see that article just click on the part of the line that says: "Click here for the Best Minerals XXXXX..."
[Rock Currier 2012]

Buergerite is currently currently not a recognized species. It was recognized as a species in 1966 when specimens were abundant compared to today but, in 2011 was renamed fluor-buergerite because of its fluorine content in 2011. The reason this name is maintained here in the tourmaline group is because of the very many specimens in collections around the world. It will take generations for most of the labels to be corrected.
Henry, D., Novák, M., Hawthorne, F.C., Ertl, A., Dutrow, B.L., Uher, P. & Pezzotta, F. (2011): Nomenclature of the tourmaline supergroup minerals. Am. Mineral., 96, 895-913.

Chromium-dravite: Trigonal: Click here for Best Minerals Chromium-dravite.
Na(Mg₃)Cr³⁺₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH) This is the only picture of Chromium-dravite we have in our database at this time (20 April 2013). The chromium-dravite are the green grains in the rock.


Chromium-dravite, Zaonezhie peninsula Karelia Republic, Russia 2cm tall	© 2007, JGW

Chromo-alumino-povondraite?: Trigonal: Click here for Best Minerals Chromo-alumino-povondraite.
Na(Cr₃)Mg₂Al₄(Si₆O₁₈)(BO₃)₃(OH)₃O
This is the only image we have of this mineral. It is not clear which part of the image shows chromo-alumino-povondraite and which part is tremolite.


Chromo-alumino-povondraite & tremolite Balmat, New York, USA FOV 1.5mm	© Vincent Bourgoin 2012

Darrellhenryite: Trigonal, click here for best minerals darrellhenryite.
Na(LiAl₂)Al₆(BO₃)₃Si₆O₁₈(OH)₃O

Mindat lists only one locality for this new tourmaline group member. The type locality for this mineral is Nová Ves, Český Krumlov, South Bohemia Region, Bohemia (Böhmen; Boehmen), Czech Republic. Mindat has no pictures of this mineral (May 2013)

Dravite: Trigonal: Dravite-Elbaite Series, Dravite-Schorl Series. Click here for Best Minerals Dravite.
Na(Mg₃)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH) Quite a few nice specimens are pictured in the dravite article.


Dravite, Reese Farm, Gouverneur, New York, USA 1.5cm tall	© 2002 John H. Betts

Elbaite: Trigonal: Elbaite-Liddicoatite Series, Dravite-Elbaite Series, and the Elbaite-Schorl Series. Click here for Best Minerals Elbaite, Afghanistan to Nigeria and here for Best Minerals Elbaite, Pakistan to Zambia. Many valuable specimens shown here.
Na(Li _1.5Al_1.5)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)


Elbaite & Quartz, Queen Mine, Pala, San Diego Co. California, USA ~17cm wide	© J.Ralph

Feruvite Trigonal: The Fe2+-analogue of uvite. Click here for Best Minerals Feruvite.
Ca(Fe²⁺)₃MgAl₅(Si₆O₁₈)(BO₃)₃(OH)₃(OH)
There are only 14 localities for this tourmaline species but we have pictures of only two specimens from a Japanese locality.


Feruvitre & diaspore, Kiura mine, Saeki city, Oita prefecture, Japan 3.6cm	© R. Tanaka

Fluor-buergerite Click here for Best Minerals fluor-buergerite. Mindat currently lists only four localities for this mineral (2013)
Na(Fe₃⁺³)Al₆(Si₆O₁₈)(BO₃)₃O₃F


Fluor-buergerite 15cm wide	© Rob Lavinsky

Fluor-dravite: Trigonal: The F analogue of dravite. Click here for Best Minerals Fluor-dravite.
Na(Mg₃)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃F


Fluor-dravite	© Chamberlain

A 3.5cm specimens of fluor-dravite from Cream of the Valley Road, Gouverneur, St. Lawrence Co., New York, USA

Fluor-elbaite: Trigonal: The F-analogue of elbaite. Click here for Best Minerals Fluor-elbaite.
Na(Li _1.5Al_1.5)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃F


Fluor-elbaite, 1.7cm, Cruzeiro mine, M.G, Brazil	©

Fluor-feruvite: The hypothetical F-analogue of feruvite. Click here for Best Minerals Fluor-feruvite.
Ca(Fe²⁺)₃MgAl₅(Si₆O₁₈)(BO₃)₃(OH)₃F
Fluor-feruvite is listed in Mindat's locality database from only one locality: Fort Hope pegmatite field, Fort Hope, Kenora District, Ontario, Canada. We have no images of this mineral and list it as the hypothetical fluorine analogue of feruvite.

Fluor-liddicoatite, Trigonal, the F-analogue of liddicoatite. Click here for Best Minerals Fluor-liddicoatite.
Ca(Li₂Al)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃F


Fluor-liddicoatite to 7cm. Anjanabonoina pegs, Betafo Dist. Antananarivo Province, Madagascar	© E. Marini

Fluor-schorl: Trigonal: The F-analogue of schorl. Click here for Best Minerals Fluor-schorl.
Na(Fe²⁺₃)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃F


Fluor-schorl	© Mills

Foitite: Trigonal: A vacancy-dominant member of the Tourmaline Group.
Correct identification is only possible by suitable analytical methods. Click here for Best Minerals Foitite.
(□,Na)(Fe²⁺₂Al)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃OH


Foitite cap on liddicoatite	© Matteo

A liddicoatite crystal with a foitite cap and a schorl base 8.1mm, Rosina vein, San Piero in Campo, Campo nell'Elba, Elba Island, Livorno Province, Tuscany, Italy

Liddicoatite: Trigonal: Elbaite-Liddicoatite Series. Click here for Best Minerals Liddicoatite.
Ca(Li₂Al)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)
Note on the nomenclature: the "liddicoatite" holotype (Dunn et al., 1977) is F-dominant on the W-site, although the originally suggested formula was OH-dominant. Therefore the type material has been redefined as fluor-liddicoatite (Henry et al., 2011); "liddicoatite" is currently a non-approved species. Most "liddicoatites" appear to be F-dominant, and therefore fluor-liddicoatite. Note on the nomenclature: the "liddicoatite" holotype (Dunn et al., 1977) is F-dominant on the W-site, although the originally suggested formula was OH-dominant. Therefore the type material has been redefined as fluor-liddicoatite (Henry et al., 2011); "liddicoatite" is currently a non-approved species.

Magnesiofoitite: Trigonal: Click here for Best Minerals magnesiofoitite.
(□,Na)(Mg₂Al)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)


Magnesiofoitite & quartz, 6.2cm	© Jiangbin

Huya W-Sn-Be deposit (Pingwu beryl mine), Huya township, Mt Xuebaoding, Pingwu Co., Mianyang Prefecture, Sichuan Province, China

Darrellhenryite: Trigonal: Click here for Best Minerals darrellhenryite.
Na(LiAl2)Al₆(BO₃)₃Si₆O₁₈(OH)_3O

There are no current photos of darrellhenryite on Mindat. Mindat currently lists only one locality for this mineral (May 2013). The type locality for this mineral is Nová Ves, Český Krumlov, South Bohemia Region, Bohemia (Böhmen; Boehmen), Czech Republic.

Olenite: Trigonal: Click here for Best Minerals Olenite.
Na(Al₃)Al₆(Si₆O₁₈)(BO₃)₃O₃(OH)


Olenite, Curiglia, Varese Province, Lombardy, Italy	© Sarah Sudcowsky

Oxy-dravite: Trigonal: Click here for Best Minerals Oxy-dravite.
Na(MgAl₂)MgAl₅(Si₆O₁₈)(BO₃)₃(OH)₃O


Oxy-dravite, Alto Chapare District, Cochabamba Department, Bolivia	© 2008, JGW

Oxy-rossmanite: Not yet approved by the IMA. A preliminary working name for a hypothetical new member of the tourmaline group. Click here for Best Minerals Oxy-rossmanite.
☐(LiAl₂)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃O
A preliminary working name for a hypothetical new member of the tourmaline group. Not an IMA approved mineral.

Oxy-schorl: Trigonal: Click here for Oxy-schorl.
Na(Fe²⁺Al)₃Al₆(Si₆O₁₈)(BO₃)₃(OH)₃O
"Schorl" with O>OH,F on the W site; not uncommon, but can be reliably identified only from detailed and quantitative chemical analyses.
Originally used as a working name and published without approval, then finally approved in 2011. IMA status: Approved 2011

Povondraite: Trigonal: Click here for Best Minerals Povondraite.
Na(Fe³⁺₃)Mg₂Fe³⁺₄(Si₆O₁₈)(BO₃)₃(OH)₃O


Povondraite 7cm wide	© Alfredo Petrov

Rossmanite: Trigonal, Vacancy-dominant member: Identification only possible with quantitative chemical analysis and/or crystal-structure refinement. Click here for Best Minerals Rossmanite.
☐(LiAl₂)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)


Rossmanite xl 2.2cm	© Kohorst

At least its mostly rossmanite. It has a yellow elbaite base with a central portion of white rossmanite with a black foitite cap.

Schorl: Trigonal: Elbaite-Schorl Series, Dravite-Schorl Series. Click here for Best Minerals Schorl.
Na(Fe²⁺₃)Al₆(Si₆O¹⁸)(BO₃)₃(OH)₃(OH)


Schorl & Quartz 10.5cm, Erongo Mountain, Erongo Region, Namibia	© Schnaitmann

Tsilaisite : Trigonal: The OH analogue of fluor-tsilaisite. Click here for Best Minerals Tsilaisite.
Na(Mn²⁺)₃Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)


Tailaisite, FOV 1.3mm	© Yaiba Sakaguchi

Vanadium-dravite: Synonym of Oxy-vanadium-dravite. Click here for Best Minerals Vanadium-dravite.
Na(Mg,Fe²⁺)₃(V³⁺,Cr³⁺,Al)₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)


Vanadium-dravite, FOV 2.5mm	© 2008, JGW

Tschermakite series (5 replies)

Olav Revheim — Fri, 25 Feb 2011 12:07:03 +0000

First Draft

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Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

The Tschermakite series minerals are minerals in the Amphibole group, see Amphibole Group main article for an overview of the group. The series contains the following minerals:

Aluminotschermakite
☐Ca₂(Mg₃Al₂)Si₆Al₂O₂₂OH₂

Alumino-ferrotschermakite
☐Ca₂(Fe₃Al₂)Si₆Al₂O₂₂OH₂

Ferri-Ferrotschermakite
☐Ca₂(Fe₃Fe₂)Si₆Al₂O₂₂OH₂

Ferritschermakite
☐Ca₂(Mg₃Fe₂)Si₆Al₂O₂₂OH₂

Ferrotschermakite
☐Ca₂(Fe₃FeAl)Si₆Al₂O₂₂OH₂

Tschermakite
☐Ca₂(Mg₃FeAl)Si₆Al₂O₂₂OH₂

The tschermakite-series of minerals is a series of rockforming minerals not known in specimens attractive to collectors. Tschermakite can be found in a wide range of geological environments, and in the 44 entries in Mindat includes calc-sislicate rocks, sulphide ores, gabbroes, vulcanic rocks as well as 3 meteorites. An extended literature search in petrografic and mineralogical literature would undoubtedly yield several tschermakite locations not currently included in the Mindat database, but since these minerals are rock-forming minerals, not all of them would qualify as a mineral occurance from a collector's point of view.

The tschermakite-series is closely related to the hornblende-series and has a slightly higher Al/Si proposion as well as pargasite-series(which is richer in Na).

The various Tschermakite-series minerals are identified on the relative distribution of Mg, Fe²⁺, Fe³⁺ and Al in the C position. Tschermakite itself probably is relative common, but is not often identified. This has to do with the cost and complexity in making a positive identification, and that accurate identification of the specimen has limited value for petrologists or ore-geologists. Also, the chemical environments in which Tschermakite is found are normally not that special or sexy, thus reducing the interest to invest time and money to identify the mineral. For mineral collectors, the cost of having the mineral identified will always exceed the value of the mineral specimen.

Some of the other end members in the series such as alumino-ferrotschermakite, ferritschermakite and ferri-ferrotschermakite will require rather special environments to form, and are as pr. 2008 hypotethical end members of the series, not described from nature. See Minerals not found in nature- Mindat message board

Tschermakite series minerals will not normally be collected by other collectors than the most enthusiastic systematic collectors, whether individuals or museums. Specimens will not be expensive unless some hitherto great new locations are discovered.

Aluminotschermakite?
Tschermakite
Tanzania
Kilimanjaro Region, Mt. Kilimanjaro, Longido


8,7 cm crystal Tschermakite	© Christian Bracke


4 cm FOV. Aluminotschermakite?	© JGW


4,7x4,5 cm Tschermakite	© Sobolewski

Both Aluminotschermakite and tschermakite are reported as occuring in the anyolite mines of Longido, Mt Kilimanjaro, Kilimanjaro Region, Tanzania. Most collectors are more familiar the red rubies embedded in the beautiful green zoisite that is the anyolite rock. The tschermakite is the black specks disturbing the nice green colour. Mindat defines the rock anyoite as « ... a metamorphic rock consisting of a granular mass of bright green chrome-zoisite with minor black tschermakite (commonly both as grains a few mm diameter), containing conspicuous coarse porphyroblasts of corundum (var. ruby) which may be up to several centimetres across.

As a generic petrographic description of this rock would be a rather clumsy mouthful, (something like "corundum-tschermakite zoisiteite" ) it has been given a more euphonious name descriptive of its striking colour in the language of the people living in the area of its type locality in Tanzania.». The rock name anyolite is derived from the word "Anyole" which is the Maasai word for green.

The zoisite/corundum/amphibole (anyolite) rock occurs in two outcrops, as veins no thicker than a few decimeters to a meter. It is believed that the two anyolite outcrops are connected as a single folded vein. The original mine consists of a ramp at 50 degrees and a dozen horizontal galleries operating through the same vein. The galleries are now in a pitiful state and the mine abandoned (as of 2000). Cuttings are not removed and landslides are frequent. The other outcrop ("Kijiji" ) was opened around 2000.

At the outcrops, mineralogical zonation is clearly visible;

1) serpentinized peridotite
2) A (phlogopite?) mica zone +/- gedrite, enclosing the ruby bearing amphibolite and anyolite
3) Dark amphibolite
4) Anyolite, constituting the core of the vein and with the following facies evident:
4a) massive anyolite with little or no amphibole
4b) "leopard" anyolite with black amphibole spots
4c) "zebra" anyolite with black amphibole stripes

Ruby ocurs as spots or anhedral crystals in thin hexagonal tablets. It is present in the anyolite as as well as in the amphibolite. The crystals can reach about fifteen centimeters in diameter.

The amphibole is generally considered as tschermakite both in Mindat and other mineralogical webpages as well as different dealers websites. The amphibole has also been named aluminotschermakite (Jochen Hintze (2010) Lapis, 35, #12, 15-19. ) but this identification is questioned due to lack of references with analytical data.

In his doctorial thesis: “Geology of Sapphire and Ruby Deposits -The example of the John Saul Ruby Mine, Mangare area, Southern Kenya” PhD Thesis, University of Nantes, Cedric Simonet, January 2000"Cedric Simonet gives a fairly detailed description of the ruby occurances at Longido including a series of chemical analysis' of the amphiboles.

He identifies three amphiboles in these rocks:
1) In the serpentinite host rock: Magnesiohornblende - 2 microprobed samples giving the following normalized formula (Na_0,34,K_0,04)_0,38Ca_1,82(Mg_4,34,Fe_0,45)_4,89 (Si_7,17Al_1,13)_8,3O₂₂(OH)₂ (average of 2 samples)
2) In the mica layer: An orthoamphibole optically indentified as “gedrite” occurs in the mica zone, probably as an alteration product of clinoamphiboles.
3) In the anyolite vein: 4 microprobed samples giving the following normalized formula: (Na_0,71,K_0,06,Ca_0,05)_0,82 (Ca_1,87, Mg_0,12, Mn_0,01)_2,00((Mg_2,91,Fe_0,87Ti_0,01,Cr_0,06,Al_1,15)_5,00 (Si_5,89Al_1,11)_8,00O₂₂(OH)₂.

The amphibole from the anyolite analysed by Dr. Simonet contains Si=5,89, Mg/(Mg+Fe) =0,91 and (Na,K)>0,5. According to the identification tables listed in Nomenclature of amphiboles: Report of the subcommittee on amphiboles of the International Mineralogical Association, commission on new mineral names (Leake et al. 1998). this amphibole classifies as pargasite, not tschermakite.

The amphibole in the anyolite rock is consequently known under three 3 different names. It is the same amphibole, but it is still possible that local variations in composition creates differnet mineral species. Afterall, all it takes to get a tshermakite from the pargasite analysed by Dr. Simonet is a reduction of the Na content from 0,7wt% to 0,4wt%.

Ferri-Ferrotschermakite
Sweden
Kopparberg, Ljusnarsberg, Västmanland Kaveltorp


4 cm sample Ferri-Ferrotschermakite?	© 2008, JGW

Kaveltorp is one of the many metamorphic sulphide ores in the vicinity of Kopparberg ( the name meaning Mountain of Copper). The document «Iakttagelser angående mineralens paragenes och successionen i Kaveltorp. (With an English summary)» by Magnusson, N.H.(1930) does assumingly provide a good reference to the mineralogy in the mine. Unfortunately, I do not have access to this paper. Magnussons paper was written pre-IMA amphibole nomenclature, and consequently before the current definition of ferri-ferrotschermakite. It is therefore unlikely that his paper will shed sufficiently detailed light on the composition of the amphibole from Kaveltorp.

Ferri-ferro tschermakite with it's current definition l is a theoretical end-member not yet described from nature. It is therefore rather unlikely that this specimen is correctly identified, and it is also unlikely that ferri-ferrotschermakite is found here or anywhere else for that matter.

Ferrotschermakite
Australia
Victoria, Dookie, Dookie Mineralogical Reserve quarry Fast Navigation for finished Best Minerals articles.


Ferrotschermakite, 6mm FOV	© Judy Rowe

Reference: Museum Victoria Collection.

Tschermakite
Italy
Campania, Naples Province., Somma-Vesuvius Complex, Monte Somma, San Vito, Ercolano, San Vito quarry


Tschermakite, 1,2 mm FOV	© luigi chiappino

The San Vito Quarry is an abandoned pumice quarry that has been very rich in minerals. It is a part of the general Somma-Vesuvius area which is a composite central volcano composed of an ancient stratovolcano, Mount Somma, and more recently by a cone, the Vesuvius. The age of the oldest products in outcrop is about 25,000 years.The latest round of activity seems to have ended with the eruption of March 1944. This eruption was the beginning of a resting phase characterized by modest signs of seismic activity and fumarole (Arno et al., 1987).
More than 230 species has been found in this area, and is one of the most interesting places in Europe. There are in principle four different mineral forming environments, each with a different mineral assemblage;
I. Minerals that are found in the ejected limestone blocks of Monte Somma.2
II. Pneumatolytic minerals formed in cavities of leucotephrites and conglomeratic blocks ejected by Monte Somma and Vesuvius, or coating the walls of ancient lavas.
III. Fumarolic products.
IV. Minerals that occur as rock constituents of Vesuvius and Monte Somma.
Amphibole minerals can be found in all of these mineral forming environments
Tschermakite is found as micro-crystals in cavities in the rock.

Olav Revheim Feb 24th 2011

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Topaz (12 replies)

Harjo Neutkens — Thu, 17 Feb 2011 15:46:00 +0000


Topaz, Ekaterinburgskaya (Sverdlovskaya) Oblast', Urals. scale 1 inch, rule at 1 cm	©

El Topacio

1.
Yo te invito al Topacio,
a la colmena de la piedra amarilla,
a sus abejas,
a la miel congelada del topacio,
a su dia de oro,
a la familia
de la tranquilidad reverberante:
se trata de una iglesia
Minima, establecida en una flor,
como abeja,
como la estructura del sol,
hoja de otono
de la profundidad mas amarilla,
rayo a rayo, relampago a corola,
insecto y miel y otono
se transformaron en la sal del sol:
aquella miel, aquel tremblor del mundo,
aquel trigo del cielo
se trabajaron hasta convertirse.

2.
Cuando se toca el topacio
el topacio de la toca:
despierta el fuego suave
como si el vino en la uva
despertara.
Aun antes de nacer, el vino claro
adentra de una piedra
busca circulacion, pide palabras,
entrega su alimento misterioso,
comparte el beso de la piel humana:
el contacto sereno
de piedra y ser humano
encienden una rapida corola
que vuelve luego a ser lo que antes era:
carne y piedra: entidades enemigas

Pablo Neruda

Topaz

Topaz, honoured by the great poet Neruda with a beautiful sonnet, called "captured sunlight" by the great gemmologist Gübelin and already in the 12th century abbess Hildegard von Bingen described the stone as having a colour closer to that of gold then to yellow.
The classic image of Topaz is indeed the one of a radiant and uniquely yellow stone. Nowadays however it seems that a vibrant blue colour is getting more and more the archetypal colour of Topaz.
The palette of Topaz colours however is far richer then just blue and yellow; we have fantastic pink Topaz from Katlang, silvery Topaz from Spitzkopje, intense blue from Virem da Lapa, golden yellow from the Schneckenstein, sherry brown from the Wah Wah mountains etc etc........the rarest colour for Topaz is arguably red, only a handful of crystals are known, like the famous red Sanarka Topaz in the collection of the Fersman Museum in Moscow.
Quite often the colour of Topaz is industrially enhanced by means of irradiation or heating.
The sizes of Topaz crystals vary considerably, from the splendid micromounts from the Eifel region in Germany up to giants from Brazil (like for instance a Brazilian Topaz in the American Museum of Natural History, measuring 80x60x60cm and weighing 300kg, and that with gem quality! and the Naturhistorisches Museum in Vienna has a cut gem weighing 585,000 carats)
Topaz is quite hard, 8 on Mohs scale, but the perfect cleavage makes the crystals vulnerable. When mining specimens many crystals easily fly off otherwise good specimens, and cut and set stones can easily crack when hit against a hard surface.
Usually Topaz crystals have little to hardly any inclusions, although there are exceptions to that rule, like for instance the Schneckenstein Topazes, where only a small percentage was suitable for cutting, most of the stones had too many inclusions.

In almost all important pegmatite or greisen localities worldwide Topaz is being found: Brazil, Madagascar, Mozambique, Namibia, Nigeria, Sri Lanka, Russia, Ukraine, USA, Afghanistan and Pakistan. Topaz from many of these countries stand out because of their size and quality. Even more important for the gem industry are secondary placer deposits that supply stones for cutting into gems, like the deposits of the Kamenka river in the Urals, the Topaz hill from Katlang or the gravels from Ouro Preto with their famous imperial Topaz.

A good specimen from a classic locality will command very high prices on the market, especially the ones from Sanarka, the Schneckenstein, Yekaterinburg, California, Ouro Preto and others.
A good twenty years ago the market started to almost flood with very high quality Topaz specimens from Pakistan and Afghanistan. In recent years this seems to have slowed down a bit so also these specimens are getting more expensive.
Recently more and more Topaz crystals have started to come to us from new horizons like Burma, China and Namibia and we will see what new localities for these beautiful crystals lie ahead of us

Topaz
Afghanistan
Laghman Province (Lagman Province; Nuristan)


Topaz 3,6cm	© John Sobolewski


Topaz ?cm	© 2002 Thames Valley Minerals

Nuristan province sensu strictu (http://www.mindat.org/loc-135473.html) became officially recognised in 2001 (wikipedia) or 2004 (statoids.com), but was already known for 10 years. It was formed from the northern parts of Laghman Province and Konar (Kunar) Province.
The capital of the Nuristan Province is Nuristan, however, "Nuristan" is also the traditional name for the region that encompasses these three current provinces (i.e., NE Afghanistan) and the name is still often used in that fashion.

Topaz
Afghanistan
Nangarhar Province (Ningarhar Province), Darra-i-Pech (Pech; Peech; Darra-e-Pech) Pegmatite Field


Topaz crystals to 3cm	© 2002, Jesse Fisher


Topaz crystal 0,9cm	©

Pech, Peech and Darri-i-Pech (also spelled Darrah Pech, and sometimes Page) are the same place. "Darrah" means "valley", so in English the location name is "Pech Valley." Many Afghanis will still use the name "Nuristan," in a traditional sense, to mean all of NE Afghanistan. This traditional meaning of the place name "Nuristan" is not to be confused with the current Nuristan Province, which covers only a portion of "Nuristan" in the traditional sense.

Topaz
Afghanistan
Nuristan Province (Nurestan Province; Nooristan Province; Nuristan), Paprok


Topaz crystal 2,5cm	© www.exceptionalminerals.com


Topaz crystal 3cm	© H. Obodda

Info needed.

Topaz
Argentina
Catamarca, Belen Department, Papachacra


Topaz crystal 2,8cm	© Tony H Gill


Topaz crystal 4,5cm	© Tony H Gill

Info needed.

Topaz
Argentina
Santa Cruz, El Chaltén


Topaz crystal 3,4cm	© www.exceptionalminerals.com

A small find of Golden Topaz crystals found in 2008 during a trip to Argentina and the few specimens that were brought back appeared at the Tucson Show. The trip and discovery are written about in The Mineralogical Record,
Jan-Feb 2009, Volume 40, Issue Number 1 and in Lapis Magazine by Robert Brandstetter, one of the discoverers. Most of the find consisted of jaggedly etched gem Topaz crystals that were loose in the pocket. Only two or three specimens featured the Topaz on Quartz matrix.

Topaz
Australia
Queensland, Tablelands Region, Mt Surprise


Topaz 3cm	© R. Bottrill


Topaz 3,5cm	© Dan & Diana Weinrich Minerals

Info needed.

Topaz
Australia
Tasmania, Moina District (Middlesex District)


Topaz 2,3cm	© Andrew Tuma


Topaz 1,5cm	© R. Bottrill 2006

Two localities for good Topaz specimens:

Dolcoath hill quarry ia a small roadmetal quarry in sandstone with narrow tin-topaz-tungsten veins.
Relatively good topaz crystals (colourless to pale yellowish) occur in clay pockets.
Located about 200 m W of the All Nations mine and less than 2 kilometers southeast of the Shephard and Murphy mines.

The Moina mine worked two well defined veins up to 200 mm wide, containing bismuthinite and wolframite in a quartz matrix, with topaz and fluorite, in pegamtites near the top of a biotite granite host (Reid, 1919). Bismutite, tungstite and ferritungstite were also recorded in the oxidised zones. Bismuthinite reportedly occurred in long bladed crystals and delicate acicular forms. Numerous small wolframite-quartz veins occur in the quartzite overlying the granite. High quality smoky quartz crystals to 150 mm long, some enclosing bismuthinite and wolframite, occur in the lodes. The deposit has been developed in a shaft, open cut, adit and trenches, and proved the lode continuous over 100 m vertically.
Recent years have seen the mine being worked for mineral specimens, mainly topaz and quartz, and is currently under lease and being worked by John Wilson and Richard Wolfe.
There are three levels of workings still visible, with most activity centered around the top and bottom levels. The top level consists of a small adit that has to be pumped out before entering, where pockets of clay can provide some stunning gemmy blue topaz crystals.

Topaz
Austria
Salzburg, Hohe Tauern Mts, Untersulzbach valley, Leutachkopf Mt., Stocker Alp


Topaz, Dickite FOV 0,36cm	©


Topaz FOV 0,5cm	©

Topaz is very rare in the Alpine clefts. On the slopes of Leutachkopf mountain some of the best Alpine Topaz specimens have been found.
The locality was discovered by Alois Steiner in 1983. Many years earlier, in the 1960s, Topaz was found by Theodor Fischer in a block that was found on the valley floor. The exact provenance of the block however remained uncertain.
In 1983 Lois Steiner was looking for clefts at the Stocker Alp area on the Leutachkopf when it suddenly started to rain. When the rain started to get worse he sought shelter under an overhanging rock. To kill the time he started to inspect the Kyanite-Quarzite rock surrounding him, he then saw some odd shaped crystals and decided to work the rock. He came home that day carrying some of the best Topaz specimens ever found in an Alpine cleft, with yellow Topaz crystals up to 2,5cm long.

Topaz
Brazil
Bahia, Brumado (Bom Jesus dos Meiras)


Topaz Quartz 3,8cm	© fabreminerals.com


Topaz, Quartz 4,75cm	© Jasun McAvoy

Very attractive pink Topaz on Quartz, recent find.

Topaz
Brazil
Espírito Santo, Mimoso do Sul, Mimoso do Sul Mine


Topaz crystal 5,6cm	© Edwards Minerals


Topaz 6,5cm	© Fernandes Edgar's

Info needed.

Topaz
Brazil
Minas Gerais, Jequitinhonha valley, Capelinha


Topaz scale 1inch, rule 1cm	©


Topaz scale 1inch, rule 1cm	©

Info needed.

Topaz
Brazil
Minas Gerais, Jequitinhonha valley, Itinga


Topaz 3,3cm	© fabreminerals.com


Topaz 5cm	© fabreminerals.com

Located in the Araçuaí Pegmatite District, Eastern Brazilian Pegmatite Province. Locality for etched Topaz with a very attractive blue colour.

Topaz
Brazil
Minas Gerais, Jequitinhonha valley, Padre Paraíso


Topaz 4,8cm	© Rob Lavinsky


Topaz 4,1cm	© Rob Lavinsky

Info needed.

Topaz
Brazil
Minas Gerais, Jequitinhonha valley, Virgem da Lapa


Topaz crystal 4,4cm	© www.exceptionalminerals.com


Topaz 5,8cm	© Russell G. Rizzo


Topaz 6,6cm	© Dan & Diana Weinrich Minerals


Large Topaz	©


Topaz crystal 3cm	© www.exceptionalminerals.com


Topaz crystal 6,3cm	© www.exceptionalminerals.com

A famous granite pegmatite locality belonging to the Araçuaí Pegmatite District, Eastern Brazilian Pegmatite Province.
Some of the most beautiful blue Topazes have come from Virgem da Lapa, and they sometimes have a considerable size. A fine example with the best blue colour at 10kg is a crystal in the collection of the Museum of Natural History of Paris.

Topaz
Brazil
Minas Gerais, Ouro Preto


Topaz 5,1cm	© fabreminerals.com


Topaz 4,3cm	© fabreminerals.com


Topaz 5cm	© Rob Lavinsky


Topaz 1,6cm	© Rob Lavinsky

Ouro Prêto mines produce orange to pinkish-purple topaz. Often the stone has been confused with the more common citrine (which is made by heating amethyst) found profusely in other Brazilian localities. However, topaz is readily identified by its superior hardness, density, and brilliance, as well as by a pronounced basal cleavage. In the early days topaz was the only gem of importance found near Ouro Prêto. Honouring Brazilian royalty, the gemstone was frequently referred to as “imperial” topaz. Later some sources called it “precious” topaz. Both terms have endured, partly because gem merchants wish to impart to customers the difference between gem topaz and citrine quartz.
Common topaz crystals are prisms which generally measure from 5 to 3 centimeters. The largest reportedly measures 50 by 8 centimetres and probably a score of crystals have been found in lengths over 15 centimetres. The larger specimens often were broken along cleavages, however, and little care was taken to keep the pieces of each crystal together for repair; thus few such giants exist intact today.
In addition, nearly all larger crystals are heavily flawed and contain little if any cutting material. An exceptionally large and rich golden brown topaz is in the collection of the Los Angeles County (California) Natural History Museum. It is 28 centimetres long.
Ouro Prêto has consistently been the world’s major source of golden topaz. Tons of crystals have been mined in the low hills west of town, but only a very few out of each 1000 crystals produce a facet-grade gem weighing more than one gram. Rare crystals with transparent sections of a remarkable sherry or muscatel colour sometimes occur and a few produce flawless 100-carat stones of incredible beauty. When peach-hued prisms are placed in ovens and heated, a fraction of them change to pink. This color transition is permanent—but at the risk of fracturing the gems. [Dr Peter Bancroft, Pala International]

Topaz
Burma (Myanmar)
Mandalay Division, Sagaing District, Mogok


Topaz crystal 3,5cm	© Rob Lavinsky


Topaz 2,1cm	© Rob Lavinsky


Topaz 8,5cm	© Rob Lavinsky


Topaz crystal 4,3cm	© 2006, Jesse Fisher


Topaz crystal 1,5cm	© Tony H Gill


Topaz 2cm	© Vítězslav Snášel

Info needed.

Topaz
China
Hebei Province, Chengde Prefecture


Topaz 3cm	© Jiangbin


Topaz 3,2cm	© Jiangbin

Info needed.

Topaz
China
Yunnan Province, Gaoligong Mts (Gaoligong Shan), Nujiang Autonomous Prefecture


Topaz crystal 1,8cm	© fabreminerals.com


Topaz crystals to 1,3cm	© Tony H Gill


Topaz crystal 3,5cm	© 2006, Jesse Fisher


Topaz crystal 2cm	© Jiangbin

Highlands west of the Nu river (Nu Jiang) valley.
Located in northwestern Yunnan Province, close to the border to Myanmar (Burma).

Topaz
China
Yunnan Province, Wenshan Autonomous Prefecture


Topaz crystal 4cm	© Rob Lavinsky


Topaz 8,4cm	© Rob Lavinsky

Info needed.

Topaz
Czech Republic
Bohemia (Böhmen; Boehmen), Karlovy Vary Region, Horní Slavkov (Schlaggenwald)


Topaz, Quartz 5,5x3cm	© G. van der Veldt


Topaz, Cassiterite 10x9cm	© A.Tomek

Info needed.

Topaz
Czech Republic
Bohemia (Böhmen; Boehmen), Ústí Region, Krupka (Graupen), Krušné Hory Mts (Erzgebirge), Knöttel (Knötel; Knödel) area, Krupka (Graupen)


Topaz, Quartz 4x6cm	© Petr Fuchs


Topaz crystal 1cm	© Petr Fuchs

Granite stock with an aureole of Mo-Sn-W bearing quartz veins, located about 1 km ENE of Krupka.
Several localities for Topaz.

Topaz
Finland
Etelä-Suomen Lääni, Orivesi, Eräjärvi area, Viitaniemi pegmatite


Topaz 2,5x2,5cm	© JA


Topaz 8,4x6,5cm	© Rob Lavinsky

Info needed

Topaz
Germany
Bavaria, Franconia, Fichtelgebirge, Tröstau, Leupoldsdorf, Fuchsbau quarry

One of the most beautiful Topaz specimens from Germany came from the Fuchsbau quarry. An 8cm tall dark smoky Quartz crystal with a squat 4cm large blue Topaz on the side.
If anyone could help us with a photo of a specimen from this locality we would be very pleased ;-)

Topaz
Germany
Bavaria, Franconia, Fichtelgebirge, Weißenstadt, Großer Waldstein Mt., Reinersreuth Quarry (Köhlerloh)


Topaz 0,6cm	© Stefan Meier


Topaz, Orthoclase, 3,8x4,8cm	© K.Gerl

A quarry in granite with pegmatite inclusions, disseminated by quartz veins.

Topaz
Germany
Rhineland-Palatine, Eifel Mts, Daun, Üdersdorf, Emmelberg Mt.


Topaz FOV 0,4cm	© Stephan Wolfsried


Topaz FOV 0,3cm	© Stephan Wolfsried

Quarry in the scoria cone of an ancient volcano. Olivine-nephelinite dykes and lava flow, with mineralizations both in cavities of the lava and in xenoliths (clay, sandstones, carbonatites, sanidinite).
Located on Emmelberg Mountain, 0.5 km south of Üdersdorf and about 6 km SSW of Daun.
Outstanding Topaz micros!

Topaz
Germany
Rhineland-Palatinate, Eifel Mts, Kelberg, Drees, Niveligsberg Mt.


Topaz FOV 0,3cm	© Stephan Wolfsried


Topaz FOV 0,3cm	© Stephan Wolfsried

Quarry in lapilli tuffs and lava slags with inclusions of xenoliths (olivine, devonian basement) and biotite crystals (up to 50 mm across).
Located on Niveligsberg mountain, 500 m NW of Drees.
Outstanding Topaz micros!

Topaz
Germany
Rhineland-Palatinate, Eifel Mts, Mayen, Ettringen, Bellerberg volcano, Caspar quarry


Topaz FOV 0,3cm	© Stephan Wolfsried


Topaz FOV 0,3cm	© Stephan Wolfsried

Active quarry. A multitude of often very rare, but well-crystallised minerals occur in xenoliths and basaltic rock.
Access is strictly limited (it was for most of the last two decades also completely forbidden).
Located between Ettringer Bellerberg and Büden mountains.
Outstanding Topaz micros!

Topaz
Germany
Rhineland-Palatinate, Eifel Mts, Polch, Ochtendung, Wannenköpfe


Topaz FOV 0,2cm	© Fred Kruijen


Topaz FOV 0,15cm	© Fred Kruijen

Active quarry. Minerals are mainly found in voids within small xenoliths.
Outstanding Topaz micros!

Topaz
Germany
Saxony, Erzgebirge, Altenberg


Pyknite, 18x8cm	© Jorge M. Alves


Pyknite, 7,5x4,5cm	© Van King

Famous old locality for the Topaz variety Pyknite. Often associated with Zinnwaldite.

Topaz
Germany
Saxony, Vogtland, Klingenthal, Kielberg Mt., Schneckenstein cliff (Königskrone Topaz Mine)


2,5cm large Topaz on Quartz	© Harjo


1,2cm large Topaz on Quartz	© DM 06


Topaz FOV1cm	© Harjo


Topaz FOV0,4cm	© Stephan Wolfsried


1,5cm large Topaz on Quartz	© 2007, Jesse Fisher


Topaz, Quartz FOV 2,6cm	© Paul De Bondt


Topaz after Orthoclase scale 1inch, rule 1cm	©


Topaz after Orthoclase 2,5cm	© Jasun McAvoy

At the start of the Topaz mining activity in 1728 the Topaz rock of the Schneckenstein (named the Königkrone mine by the discoverer of the occurrence, Christian Kraut) gained a wide recognition being the first mining endeavour exclusively for gems. This meant that it received the highest legal insurance and right from the king, Kurfürst August der Starke.
On the 27th of August 1737 the rights were installed and welcomed with great festivities.
Immediately the miners started "in good spirits and by good weather" and in no time a pound (Pfund) of quality Topaz was found.
The Topaz crystals were sold to pharmacists who shipped the crystals to gem cutters in Bohemia and Venice. The cut gems came back to Saxony as "Oriental Topaz". As late as 1740 Dr Johann Friedrich Henckel laughingly wrote that the foreigners obviously knew the Schneckenstein Topaz better than the people from Saxony themselves as they bought their stones for a way too high price.......
The Topaz from the Schneckenstein were valued throughout Europe, for instance, King George III of England had a crown made (for his wife Charlotte) including 485 cut Schneckenstein Topazes.
The colour of the Schneckenstein Topazes ranges from colourless over different shades of yellow (the most coveted are the "golden" yellow ones) to a light brown, but also greenish stones have been found.
The Topaz occur in a greisen body, druses in the greisen contain slender Quartz crystals (mostly transitional habit) on which the Topaz crystals sit, often accompanied by dark green to dark brown Tourmaline, Cassiterite, Ilmenorutile, Crandalite and Chalcosiderite. These cavities are usually filled with yellow Kaolinite.
The most common inclusions in the Topaz crystals are Cassiterite and Ilmenorutile.
Also very interesting are the Topaz after Orthoclase pseudomorphs found at the Schneckenstein.
Good Schneckenstein specimens command very high prices on the market. Because it is strictly forbidden to collect at the site no new specimens enter the market (the cliff itself is fenced-in and the surrounding forest is also restricted by the forestry department). This means that prices for a good specimen will only increase. But, who doesn't want to posses a choice Schneckenstein Topaz specimen...........

Topaz
Germany
Saxony, Vogtland, Klingenthal, Muldenberg, Saubach Fault


Topaz after Orthoclase 8,4x7,8cm	© Edwards Minerals


Topaz after Orthoclase 3,5cm	© J.Ralph

Locality famous for Topaz after Orthoclase pseudomorphs.

Topaz
Germany
Saxony, Erzgebirge, Zinnwald


Pyknite 8x10cm	© Petr Fuchs


Pyknite 8,5x6cm	© G. van der Veldt

A famous tin deposit. One part of the deposit is situated in Saxony, Germany (Zinnwald), the other in Bohemia, Czech Republic (Cinovec).
Quartz/cassiterite/wolframite stockworks, flat veins and greisens in the endo/exocontact of a granitoid cupola intrusion.

Topaz
Italy
Sardinia, Oristano Province


Topaz FOV 0,3cm	© Chinellato Matteo


Topaz FOV 0,4cm	© Enrico Bonacina

Several quarries (Conca, Funtanafigu) delivering excellent Topaz micros.

Topaz
Japan
Honshu Island, Chubu Region, Gifu Prefecture, Nakatsugawa City, Hirukawa


Topaz 2,4cm	© Rob Lavinsky


Topaz 0,7cm	© 2001 John H. Betts

An area of miarolytic cavities and pegmatites in granite quarries. Produced specimens abundantly in the past, but has almost dried up due to the quarries closing because of cheap granite imports from abroad.

Topaz
Japan
Honshu Island, Kinki Region, Shiga Prefecture, Otsu City, Tanakami-yama (Tanokami-yama)


Topaz 2,9cm	© Edwards Minerals


Topaz 3,6cm	© A&M

Granite pegmatite district, mined for centuries for its feldspar for the local ceramic industry. Crystal pockets have been almost completely worked out by local mineral collectors, and many of the dumps are overgrown with forest, so not much of collector interest is left to find here.

Topaz
Kazakhstan
Karagandy Province (Qaragandy Oblysy; Karaganda Oblast'), Airtau


Topaz 3,6cm	© Igor Savin


Topaz 8,1cm	© Igor Savin

Granitic pegmatites.
Located about 30 km south of Agadyr' settlement, the center of Shetskii area of Karagandy Province.

Topaz
Kazakhstan
Karagandy Province (Qaragandy Oblysy; Karaganda Oblast'), Ortau


Topaz 9,4cm	© Oleg Lopatkin


Topaz 9cm	© Oleg Lopatkin

Info needed.

Topaz
Mexico
San Luis Potosí


Topaz 4cm	© Tony Peterson


Topaz crystal 4,5cm	© Georges BRET


Topaz 3,4cm	© 2002 John H. Betts


Topaz crystals to 1,5cm	© sandro maggia

Info needed.

Topaz
Mexico
Zacatecas


Topaz 2,6cm	©


Topaz crystals to 2cm	© 2007, Jesse Fisher


Topaz 3,9cm	©


Topaz 3,8cm	©

Several localities for Excellent Topaz in Rhyolite.

Topaz
Mongolia
Ghorkhi massiv, Goricho


Topaz 2,9cm	© Zbynek Burival


Topaz 6,5cm	© Zbynek Burival

The locality is about 100km E from Ulaan-Baatar. The Massiv contains several hundreds of pegmatites, most of them primitive but some have a high concentration of Be, NYF and REE.

Topaz
Namibia
Erongo Region, Swakopmund District, Swakopmund, Groot en Klein Spitzkopje (Groot en Klein Spitskopje; Große und Kleine Spitzkoppe)


Topaz 4,6cm	© Rob Lavinsky


Topaz crystal 1,3cm	© 2000 John H. Betts


Topaz 3,2cm	© 2003 John H. Betts


Topaz crystals to 2cm	© Dr. Lueg 2005

Groot Spitzkopje:
Isolated granite massif elevating from a peneplain (~1000 m above sea level), 1728 m high. The Groot Spitzkopje is also called "Matterhorn of Africa". The biotite granite intruded during a late stage of the Damara orogeny (about 530 Ma, the neighboring Kleine Spitzkopje granite intruded ~ 400 Ma later). The Spitzkopje area is world famous for its pegmatite minerals, especially topaz.

Klein Spitzkopje:
Located 30 km from Usakos next to the main road to Swakopmund. Remnant of a ring complex that has extensively occurring miarolitic cavities with superb Topaz crystals (Silbertopas).

Topaz
Namibia
Erongo Region, Usakos and Omaruru Districts, Erongo Mountain


Topaz 9,6cm	© Rob Lavinsky


Topaz 4cm	© Gerhard W. Louw

The Erongo Mountain is 20 km north of the town of Usakos. Usakos is 140 km from Swakopmund on the highway between Swakopmund and Windhoek. The Erongo mountain is 65 km in diameter and stretches from Usakos to the town of Omaruru in the north.

Topaz
Nigeria
Plateau State, Jos Plateau


Topaz 1,8cm	© 2001 John H. Betts


Topaz 3,3cm	© Rob Lavinsky

Info needed.

Topaz
Norway
Buskerud, Hurum, Grimsrudbukta area


Topaz 1,6cm	© Conny Larsson


Topaz 1cm	© Olav Revheim

Spoaradic occuring miarolitic cavities in Drammens granite (a biotite granite)

Topaz
Pakistan
North-West Frontier Province, Mardan District, Katlang, Ghundao hill


Topaz crystal 2,5cm	© Kiyoshi Kiikuni


Topaz 2cm	© Rob Lavinsky


Topaz crystal 4cm	© Roger Lang 2003


Topaz crystal 2cm	© H. Obodda


Topaz crystal 2,3cm	© Tony H Gill


Topaz crystal 5cm	© J.Ralph

The Katlang Topazes were discovered in the second half of the 20th century. They are being mined from the so called "Topaz Hill", Gundao hill, an outcrop consisting mainly of re-crystallised limestones.
The crystals, usually not exceeding 3cm in length and often in a tabular habit, are encountered in veins of coarse Calcite, together with Quartz, Muscovite and Talcum. The striking pink colour have made the Katlang crystals famous around the globe and good specimens are very expensive.
In the 80s of last century the annual production of gem rough was about 30.000 carat.

Topaz
Pakistan
Northern Areas, Astor District (Astore District), Astor valley (Astore valley), Bulochi (Balochi; Balche; Bulache; Bulachi; Drot Balachi)


Topaz crystal 4,5cm	© Rob Lavinsky


Topaz crystal 2cm

A village 4 km south of the Indus River, 7 km south of Shengus. Numerous complex granitic pegmatites in the area. (Previously part of Diamar District.)

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Basha Valley (Basha Nala; Basna)


Topaz crystal 4,5cm	© 2009 Jesse Fisher


Topaz 10,2cm	© TVM

A northern tributary to the Shigar River Valley. (Descends from Mt Chogo Lungma and joins with the Braldu river to form the Shigar river).

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Braldu valley


Topaz crystal 3cm	©


Topaz crystal 1,7cm	© Rob Lavinsky


Topaz crystal 6cm	© Joe Budd Photography


Topaz 2cm	© Weinrich Minerals

Several very good localities for Topaz: Nyet-Bruk, Gyaiungu, Apo Ali Gun, Baha.

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Haramosh Mts, Chamachhu, Chamachhu Pegmatites


Topaz crystal 2cm	© Michael Shaw


Topaz crystal 1,2cm	© TVM

A village along the Gilgit-Skardu road, in the Indus valley, 10 km east of Shengus. Numerous complex granitic pegmatites in the area.

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Haramosh Mts, Shengus (Shingus)


Topaz crystal 3cm	© Jordi Deusedes


Topaz crystal 5,5cm	© Rob Lavinsky

Also spelled Shingus. A village at Km 53 along the Gilgit-Skardu Road. Numerous complex granitic pegmatites in the area. Many of the specimens attributed to here are from Sabsar or the Baralooma valley.

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Haramosh Mts, Stak Nala


Topaz FOV 3cm	© YCL


Topaz crystal 1,2cm	© CCURTO2010

Miarolitic granite pegmatites in the Stak valley in the northeast part of the Nanga Parbat – Haramosh Massif, in northern Pakistan, locally contain economic quantities of bi- and tricolored tourmaline.

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Shigar valley, Dassu (Dasso; Dusso)


Topaz 3,2cm	© finestminerals.com


Topaz crystals to 2,5cm	© Rob Lavinsky


Topaz crystal 3,5cm	© finestminerals


Topaz crystal 1,5cm	© Tony H Gill


Topaz crystals to 2cm	© 2006, Jesse Fisher


Topaz crystal 4cm	© Dr. Lueg 2005

Also spelled Dusso.
A village in the upper Shigar River Valley. Numerous complex granitic pegmatites in the area. There is also a village of the same name along the Gilgit-Skardu road, bordering the Indus River. This location is sometimes referred to as "Haramosh Dassu".

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Shigar Valley, Yuno (Yunau; Yunas)


Topaz crystal 2,6cm	© Antonio Borrelli


Topaz crystal 2,9cm	© Chinellato Matteo

A village in the upper Shigar River Valley, 8 km below Braldu and the Basha river junction, 45 km NW of Shigar, at elevations around 3,000 to 4,000 metres. Numerous complex granitic pegmatites are found in the area.

Topaz
Pakistan
Northern Areas, Baltistan, Skardu District, Skardu


Topaz crystal 11cm	© 2002 John H. Betts


Topaz crystal 4,5cm	© www.exceptionalminerals.com

A town at the confluence of the Shigar and Indus Rivers. Administrative center for the district.

Topaz
Pakistan
Northern Areas, Gilgit District, Gilgit


Topaz crystal 1,6cm	© Antonio Borrelli


Topaz 3,8cm	© Rob Lavinsky

Administrative center for the District. No mineral localities of note occur in or around Gilgit, but the town is a local center of trade in minerals and gems from the region. Mineral specimens labeled "Gilgit" are usually from elsewhere in the area.

Topaz
Pakistan
Northern Areas, Gilgit District, Haramosh Mts, Dache (Dassu; Dasu; Haramosh-Dassu; Dacha)


Topaz 5cm	© H. Obodda


Topaz crystal 2,6cm	© 2002, Jesse Fisher


Topaz 6,2cm	© Rob Lavinsky


Topaz crystal 3,5cm	© Rob Lavinsky

A village approximately 10 km NE of Hanuchal, and 10 km north of Shengus along the Indus River. Numerous complex granitic pegmatites in the area. Not to be confused with the Dache in the Astor valley, or the Dassu village in the Shigar Valley, Skardu District.

Topaz
Russia
Eastern-Siberian region, Transbaikalia (Zabaykalye), Chitinskaya Oblast', Nerchinsk (Nertschinsk)


Topaz 7cm	© 2009 Jesse Fisher


Topaz 6,4cm	© Oleg Lopatkin


Topaz, Quartz, scale 1inch, rule 1cm	©


Topaz 10x5cm	© Tony H Gill

These Nertschinsk gem mines started in 1723 are are on three peaks of the Adun-Cholon Mountains: Hoppevskaya Gora (Schorl Mountain), Sherlovaya Gora, Soktuj Gora; and further north near the Urulga River. Most locality attributions are suspect as the gem dealers are not interested.

Topaz
Russia
Far-Eastern Region, Zabytoye deposit


Topaz 13,5x11cm	© Lopatkin Oleg


Topaz 4,2cm	© Oleg Lopatkin

Greisen deposit associated with exo- and endocontacts of small granite stocks with lithium-fluorine specialization Known for large blue topaz.

Topaz
Russia
Urals Region, Middle Urals, Ekaterinburgskaya (Sverdlovskaya) Oblast'


Topaz, scale 1inch, rule 1cm	©


Topaz, scale 1inch, rule 1cm	©


Topaz, scale 1inch, rule 1cm	©


Topaz, scale 1inch, rule 1cm	©


Topaz, scale 1inch, rule 1cm	©


Topaz 2,8cm	© 2003 John H. Betts


Topaz crystal 2,5cm	© 2007 Jesse Fisher


Topaz crystal 1,5cm	© 2004, Jesse Fisher


Topaz crystal 2,6cm	© Rob Lavinsky


Topaz crystal 2,6cm	© Dan & Diana Weinrich Minerals

One of the worlds most important localities for excellent blue and brown Topaz specimens. The Topaz crystals from here command very high prices on the market.
The Topaz localities in the Urals are classics, the specimens rank amongst the best in the world. The great finds belong to the past and before the advent of Pakistani, Afghani and Brazilian Topazes every museum coveted a Urals Topaz along with an American (USA) one.
The Russian mineralogist Nikolai Iwanowitsch Kocharow (1818-1892) wrote: Around Ekaterinburgskaya one finds Topaz crystals near the village of Alabaschka near Mursinka, they occur in granite cavities. The size of the crystals varies, from tiny to several centimetres large. Usually they are blue, although sometimes they are light green or greyish white. One rarely finds Topazes from this locality that are completely colourless. They often occur here in a beauty of crystallisation rarely surpassed by foreign Topaz crystals [translation Harjo Neutkens].

Topaz
Russia
Urals Region, Southern Urals, Chelyabinsk Oblast', Ilmen Mts, Miass (Miask)


Topaz 1,3cm	© fabreminerals.com

Info needed.

Topaz
Russia
Urals Region, Southern Urals, Chelyabinsk Oblast', Plast, Kochkar' District, Kochkar' Au Deposit


Topaz crystal 1,1cm	© Tony H Gill


Topaz crystal 3,5cm	© Tony H Gill

Supergene gold deposit, hosted in Late Paleozoic granite gneisses of the Plast massif.
Locality for hard to obtain and rare pink and orange Topaz.

Topaz
Spain
Extremadura, Badajoz, Valle de la Serena, San Nicolás Mine


Topaz 2,9cm	© Angel Acedo


Topaz 1,7cm	© fabreminerals.com

Info needed.

Topaz
Switzerland
Grischun (Grisons; Graubünden), Lugnez Valley (Lumnezia Valley)

Apart from the Topaz occurrence on the slope of the Leutachkopf mountain in Austria some of the best Alpine Topazes came from clefts in Lugnez valley.
We would very much like to obtain good photographs of specimens from this locality.

Topaz
United Kingdom
Devon, North Devon, Bristol Channel, Isle of Lundy, VC Quarry


Topaz crystals 0,6cm	© Topaz


Topaz FOV 0,8cm	© Richard De Nul

Info needed.

Topaz
United Kingdom
Northern Ireland, Co. Down, Mourne Mts, Diamond Rocks


Topaz crystal 1cm	© Stephen Moreton


Topaz FOV 1cm	© Steve Rust

Info needed.

Topaz
Ukraine
Zhytomyr Oblast' (Zhitomir Oblast'), Volodarsk-Volynskii (Volodars'k-Volyns'kyy; Wolodarsk-Wolynskii)


Topaz 10cm	© INS


Topaz 5,3cm	© Oleg Lopatkin


Topaz 8x7cm	© Rob Lavinsky


Topaz 15x13cm	© Jindrich Kynicky

Old and famous pegmatite district (excellent 'heliodor' beryls and topaz, from huge pockets). North south trending belt 500-1500 meters wide and 22 km long.

Topaz
USA
California, San Diego Co., Aguanga Mountain District (Smith Mountain District)


Topaz 6,5cm	© 2009 Jesse Fisher


Topaz 7,1cm	© Rob Lavinsky

A gemstone and rare earth element (REE) pegmatite area located approximately 4 miles south of the town of Oak Grove. The area is situated along the northern and southern sides of the Aguanga Mountain ridgeline, which is the southeast spur of Palomar Mountain. The mountain has also been referred to as Smith Mountain.

The Maple Load Mine was claimed again in 1915 by Fred Rynerson who briefly worked the ledge with Henry Stenbock. Rynerson discovered one exceptionally fine blue topaz crystal which measured 1 inch tall by one half inch wide, associated with blue tourmaline, about 10 feet back along the east wall of the underground workings.

In 1935 John Wesley Ware reported that under his supervision the Ware Mine had been worked to the extent of about 2,500 feet of tunnels. The principal production was precious blue topaz, of which the mine netted several hundred pounds. Crystals of blue topaz ranging from about 1 carat in weight up to 3¼ pounds were reported to have been taken out. One crystal, which cut a 17 carat pear-shaped gem of an unusually beautiful blue color was pronounced by competent authority George F. Kunz, to be the finest blue topaz in the world. Ware also reported the production of pink, white, and golden beryls, as well as pink, green, blue, and colorless tourmaline, and what he termed "Emeralite", a beautiful Nile green tourmaline of most unusual and pleasing color, for which the mine was named.

Topaz
USA
California, San Diego Co., Ramona District, Ramona, Little Three Mine (Little 3 mine)


Topaz crystal 3,5cm	© Jesse Fisher, 2001


Topaz crystal 3,6cm	© Dan Weinrich

A gemstone and mineral specimen mine developed in pegmatite which is located 7.1 km (4.4 miles) ENE of Ramona. One of the prime locations in North America for natural blue topaz. Major finds were made in 1976 and 1991. It is important to note that spessartite labeled as from the Little Three Mine is found on the adjacent Hercules pegmatite dike, a distinctly separate deposit which is also exposed on the property.

A very fine topaz-elbaite matrix specimen weighing about 150 pounds was mined in 1905 from the Little Three Mine main dike. The specimen was placed on display for many years at the San Diego Chamber of Commerce until it was moved to the newly opened Natural History Museum. During World War II, the Navy took over the museum, and the displays were crated and stored away. The specimen hasn't been seen again, and it is said to have likely been put onto a junk barge, and dumped into the ocean.

Topaz
USA
Colorado, Park Co., Tarryall Mts


Topaz scale 1inch, rule 1cm	©


Topaz 4,7cm	© 2009 EMC

Info needed.

Topaz
USA
Idaho, Custer Co., Sawtooth Batholith/Sawtooth Mts


Topaz crystal 2,8cm	© Wm. C. van Laer


Topaz 1,9cm	© Wm. C. van Laer

Minerals occur in miarolitic cavities in Sawtooth Granite - extends into Boise and Elmore counties (see there). Wilderness area.

Topaz
USA
Nevada, Mineral Co., Fitting District, Gillis Range, Zapot Pegmatite


Topaz 18,5x17cm	© Rob Lavinsky


Topaz 2,5cm	© Allan Young

Pegmatite with hydrothermal breccia with Al-fluorides, located near Hawthorne.

Topaz
USA
Utah, Juab Co., Thomas Range


Topaz 2,7cm	© Rob Lavinsky


Topaz 3,2cm	© Chinellato Matteo


Topaz 2cm	© Rob Lavinsky


Topaz 3,7cm	© Rob Lavinsky


Topaz 5,5cm	© Rob Lavinsky


Topaz 3,8cm	© Rob Lavinsky


Topaz 4,6cm	© Rob Lavinsky


Topaz crystal 1,2cm	© Rob Lavinsky

Locality for very nice sherry coloured Topaz, found in tertiary rhyolites.
Choice Topaz comes from the Thomas Range, including localities such as Topaz Mountain (with Topaz Valley/the Cove); the Dugway Range; Keg Mountains and Drum Mountains.
Further to the south are the Wah Wah Mountains; Needle Range and Paradise Hills.
Very nice are specimens where Bixbyite or Red Beryl accompany the Topaz. A speciality for the locality are Topaz included with sand.
In 1969 Governor Calvin C. Rampton declared the sherry coloured Topaz the state gem for the state of Utah.

Topaz
Vietnam
Thanh Hoa Province, Xuan Le


Topaz 2cm	© Rob Lavinsky


Topaz crystals to 2,4cm	© Rob Lavinsky

Info needed.

Topaz
Zimbabwe
Mashonaland West, Karoi (Urungwe; Hurungwe) District, Mwami


Topaz 9,2cm	© Rob Lavinsky


Topaz 4cm	© Dan & Diana Weinrich Minerals

Located SE of Miami.
Hydrothermally kaolinized zone in a F-enriched granitic pegmatite intruded in Precambrian staurolite schists (Lomagundi system).

[Harjo Neutkens 2010]

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Tremolite (14 replies)

Olav Revheim — Fri, 25 May 2012 12:29:18 +0000

First draft

Click here to view Best Minerals T , and here for Best Minerals A to Z and here for Fast Navigation for finished first draft Best Minerals articles.

Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Fluorotremolite
☐Ca₂Mg₅Si₈O₂₂F₂

Parvomanganotremolite
☐(CaMn²⁺)Mg₅Si₈O₂₂F₂

Tremolite
☐Ca₂Mg₅Si₈O₂₂(OH)₂


Tremolite 2.7 cm	© Rob Lavinsky


Tremolite & Uvite 8cm wide	©


Tremolite 2.8 cm tall	© vasco trancoso

Tremolite is a mineral in the Amphibole group, see Amphibole Group main article for an overview of the group. Tremoliteforms a continuous series with actinolite, see Actinolite

Tremolite was first described as a new species in the late 18th century. The name of the species is derived from the Val Tremola, a valley in the canton Tessin. However, tremolite has never been found in that valley. Studies of the early literature and of the specimens preserved in old collections has clearly shown that the true type locality is the Triassic dolomite of Campolungo, Tessin (Stalder et al., 1998), an area also famous for the large corundum crystals first found there in the mid-19th century (e.g. Rovetti et al., 1994).

In the IMA nomenclature of amphiboles tremolite forms part of the tremolite–actinolite–ferro-actinolite series: Whereas usually the dividing line between two species in a continuous solid solution series is set at the 50% point, tremolite occupies only a narrow range. It is defined as having an Mg/ (Mg+Fe2+) ratio ≥ 0.9; actinolite has a ratio of 0.5–0.9 and ferro-actinolite has a ratio of less than 0.5. These limits are designed to satisfy the strong desire, expressed especially (but not solely) by metamorphic petrologists, to retain the distinction of green actinolite from colorless tremolite. Another reason is that tremolite is an important mineral in the definition of metamorphic zones, and the diagnostic color distinction so useful in the field is entrenched in the literature; a change in the definition of the mineral would have complicated the application of important previously published studies.

Tremolite is, like all the other amphibole group minerals, difficult to distinguish from some of the other minerals in the group without chemical and structural analysis. I have limited the minerals and locations described in this article to the entries in the database supported by proper analysis . This has left out several good locations where the amphibole is tentatively identified as tremolite, but I think the value of the article is higher if the information contained inside is reasonably correct. The good tremolite locations where I have not been able to positively ID are presented in the amphibole group article.
Since all amphiboles have similar physical properties, such as crystal habits, cleavage, hardness, specific gravity and so on, we often turn to color to identify the individual minerals in the amphibolites group, and more often than not, whitish or light colored amphiboles tends to be labeled tremolite. This is not a recommended practice, as many amphiboles (such as edenite, cummingtonite and antophyllite) can be light colored, and tremolite can be white, grayish, brown, yellow, green and lilac. Color is therefore not necessarily a reliable means of identification.

It is difficult to discuss any amphibole without establishing the chemical relationship to the other amphiboles. Tremolite fits nicely into the general amphibole formula of AB2C5T8O22(O,OH,F,Cl)2, having an empty A position, Ca in the B position and Mg in the C position, generating the formula Ca2Mg5Si8O22(OH)2.
In slightly different chemical environments other amphiboles can be formed rather than tremolite.
- Fe enriched environment- Fe enters the C position and the amphibole becomes actinolite ( In order to be tremolite, Mg must occupy more than 90% of the C position sites, actinolite from 10-50% Fe in the C site and ferroactinolite > 50% Fe in the C site.)
- Al enriched environment- Al enters the C and T positions and the amphibole becomes magnesiohornblende
- Na enriched environment – Na enters the A position and Al the T position and the amphibole becomes edenite
- Mg enriched environment – Mg enters the B position and the amphibole becomes cummingtonite or anthophyllite.

Consequently, in order for the amphibole to be tremolite, the geological environment must be suitable. There must be sufficient temperature and pressure to form an amphibole mineral, combined with a chemistry with a sufficient content of Ca, Mg and Si, and not too much Al, Fe og Mg. The ideal environment for tremolite formations are metamorphosed sedimentary rocks containing dolomite and quartz, and not too much of the other stuff. This combination is relatively common in greenschist-facies to amphibolite-facies calc-silicate, skarn and in some low-grade ultrabasic rocks. In any other rock, one should be even more cautious in naming an amphibole tremolite than in these rocks.

Tremolite is not a favorite amongst collectors; it is to often a dull whitish, grey color with intermingled crystal fibers without terminations. Often more interesting minerals from the same location are the focus is for collectors, leaving fibrous tremolite as the matrix on a specimen. This is definitely the case both for Outokumpu, Finland and Merelani Hills, Tanzania where uvarovite and tanzanite respectively are the favored takeaway from the location. There are nevertheless some quite stunning locations out there, in particular the green, gemmy crystals from Tanzania and the pink/lilac crystals from the East Coast of the USA. The crystal groups from Haliburton County are also nice. Individual terminated crystals can reach several centimeters from all of these locations. Good, well crystallized and nicely colored specimen may well reach prices exceeding 1000 USD, and a display with a green gemmy crystal from Tanzania, next to a large lilac Lawrence County tremolite var. hexagonite and a white terminated Canadian crystal should enable slightly more attention to this mineral than it receives today.

In rare cases, gemmy crystals from Tanzania and Canada have been faceted, but tremolite will probably never become a popular gemstone. It is too rare in gem quality, not hard enough and I suspect that the perfect cleavage has caused some grief for those trying to make tremolite gems.

Nephrite jade is a common name for tight massive amphibole that is extensively used in preparing jewelry and art objects. Tremolite may well form nephrite and provide very lightly colored jade. This article does not discuss tremolite-nephrite as I think jade deserves an article entry in its own right.

Fibrous tremolite-asbestos have previously been mined and has been responsible for numerous deaths amongst miners and people working with asbestos products. These products are thankfully banned now. Some places, like nearby Kabul, Afghanistan the soil contains so much naturally occurring asbestos fibers that people may get asbestos related diseases.

Tremolite
Afghanistan
Badakhshan Prov


Tremolite, main crystal 1,5 cm tall	© Fabre Minerals

The Badakhshan province is Afghanistan's northernmost province, and also one of the largest. It covers and area of approximatel 44,000 sq.km, roughly equal to that of Switzerland and twice the size of New Jersey. The mountin ranges Hindu Kush and Pamir lies in the heart of the province, and the highest peak of Hindu Kush, the Tirish Mir reaches 7,708m above sea level. The Badakhstan province hosts one of the most exiting and exotic mineral locations in the world, namely the Sar-e-Sang quarries where lapiz lasuli has been retieved for several thousand years.

I have found very few references to tremolite from Bandakhshan. This picture of tremolite is one of the very few, and tremolite is not listed in the Mindat database at all from Afghanistan. This does not mean that tremolite cannot be found there. The geological setting with lime bearing sediments metamorphosed to the amphibolite facies surely indicates the oppposite. The lack of recorded tremolite locations in Bandakshan I think, is more due to the limited value of the mineral, and that great collector specimens has not hit the international market yet.

This leaves a few questions for this specimen. The geology of the area clearly indicates that tremolite should be present, but the lack of documentation indicates that specimens on the quality of the pictured specimen is not readily available. I suspect that this pictured specimen may be winchite from the Koksha valley (see [www.mindat.org]), rather than tremolite.
Can anyone confirm this specimen as tremolite?.

Tremolite
Canada
Ontario, Haliburton Co., Cardiff Township, Dyno Turn Tremolite


Tremolite 9 cm wide	© Jay Vonderhey

Speaking in geological terms, Haliburton County lies in the "central metasedimentary belt" in the Grenville series of rocks. The tremolite here is formed in metamorphosed Mg-bearing marbles- dolomite marbles. Although many dolomitic marbles has originated from dolomitic sediments, this does not seem to be the case here, where it is believed that the Mg influx has originated from igneous intrusions. The silica required to form tremolite seems to be a combination of residue silica from the sediments, combined with influx from the igneous rocks. Numerous mineral locations are found in skarn or calc-silicate rocks on the border between the igneous and metasedimentary rocks, and it seems as if tremolite are found both in these skarn zones and embedded in the marble itself.

This occurance is a road cut, and it seems to be a contact type occurance where white tremolite are found in the contact zone between marble and another rock. Tremolite seems abundant at the locality.

Listed Reference for locality: Schroetter, Ralph. The Bancroft & Area Mineral Collectors Guide. Dyno Turn Tremolite. pg148, full edition.

Tremolite
Canada
Ontario, Haliburton Co., Glamorgan Township, mo Tremolite occurrence


Tremolite & Diopside ~7cm wide	© MJB, 2009

This is a largely unexplored, but apparently widespread occurrance of large clots of diopside and tremolite in marble, with some quartz. Tremolite occurs as white, gray, light blue/green, and deep smoky brown crystals to several inches, in coarse calcite and massive quartz. Colourless and brown crystals have been found in gem quality but most are fractured.
Reference: Microprobe analysis by Glen Poirier at the Canadian Museum of Nature

Tremolite
Canada
Ontario, Haliburton Co., Harcourt


Tremolite, 3.2cm	© 2001 John H. Betts

Leach (1964, p.10) mentions green gemmy material from Harcourt, in the Bancroft district, which would yield cats-eye cabs or tiny facetted stones. Reference: ontariominerals.com

Tremolite
Canada
Ontario, Haliburton Co., Monmouth Township, Wilberforce


Tremolite 6.6 cm tall	© Weinrich Minerals

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Waite(1944) mentions a deep blue marquis brilliant 0.70 ct stone from here: reference: ontariominerals.com

Tremolite
China
Hebei Province, Baoding Prefecture


Tremolite 6 cm tall	© Safaa Yu

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The location for this specimen, the Baoding Prefecture covers an area of 22,159 km², so pinpointing the location to a level of details as for the Canadian localities above is not possible. Also realizing that the Baoding area mainly consists of flat, agricultural plains, opens for a suspicion that the pictured specimen may be from the Taihang mountains further west. The rocks in the Hebei province ( covering a mere 187,700 km²) is of mainly metamorphic origin supporting the existence of tremolite. I would however like some more details on the origin and ID pf the specimen to include it in the final article due to the many amphibole minerals that may look similar to the pictured specimen.

Tremolite
Finland
Itä-Suomen Lääni, Outokumpu Cu-Co-Zn-Ni-Ag-Au ore field


Tremolite in Calcite 1cm crystal

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The Outokumpu ore lies along the western margin of a serpentinite body. Both the ore and the serpentininte body is enveloped by a carbonate/tremolite skarn. The greene chromium rich tremolite is found together with calcite, sulphides, uvarovite and chrome minerals in some areas where the skarn is in direct contact with the ore body. The rock is matamorphosed to middle amphibolite facies.

Tremolite
Kenya
Umba Valley region


4cm Tremolite xl in Calcite	© 2002 John H. Betts

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It seems as if green tremolite coloured by vanadium is found associated with the grossular variety tsavorite in the gem mines in the area. The geological environment seems similar to the Merelani hills in Tanzania, where tremolite is found in calc-silicate rocks between the dolomittic marbles and graphite bearing gneiss.

Tremolite
Madagascar
Antananarivo Province, Vakinankaratra Region, Antsirabé 2 District, Mt Ibity (Mt Bity),Ibity Commune, Ibity massif


Tremolite 2,2 cm crystal	© Rob Lavinsky

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Tremolite from Ibity has been known for a long time. The mineral identification is confirmed through testing published at Rruff.info and in other publications. Tremolite is normally found as green euhedral crystals up to a couple of cm long. The crystals is often of good quality, sometimes transparent and often without inclusions. The green color is probably due to a small iron (~2,0%) content, and consequently border line to actinolite.

Tremolite
Madagascar
Tuléar (Toliara) Province, Anosy (Fort Dauphin) Region, Taolañaro (Fort Dauphin) District, Ranomafana-South Commune


Tremolite 8 cm wide after wollastonite	© Arliguie M

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Tremolite
Norway
Nordland, Rana, Storakersvatn


Tremolite 7 cm wide after diopside	© Martins da Pedra

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Tremolite was described from several locations in Nordland by Vogt already in 1897. The tremolite is found in dolomittic marbles in caledonic rocks. Storakersvatn is the most renown location in the area, and especially the tremolite pseudomorphs after diopside can be quite attractive. These pseudomorphs is quite common in sizes exceeding 10 cm. Also regular whiteish fans of fibrous tremolite are known from road cuts along the gravel road alongside the lake. The individual fibres can be quite long. The host rock at Storakersvatn seems to be calcite cemented dolomittic sandstone.

Tremolite
Switzerland
Ticino (Tessin), Leventina, Piumogna Valley, Campolungo


Tremolite 22 cm wide	© luigi chiappino

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Tremolite is named after the Tremola Valley, not far from the Campolungo site, despite the fact that tremolite does not occure in the Tremola Valley, and due to the rock forming conditions there cannot exist either. All the earliest tremolite specimens offered to museums and collections after its discovery in 1795 came from Campolungo. The quote below shed light on the events leading up to the misunderstandings surronding the type location of tremolite:

"When, about twenty years ago, tremolite was found in the high, almost inaccessible rock cliffs of Campo Longo, opposite to the Gotthardt pass, such a fossil [= mineral] was little known from other localities. People were delighted about and amazed by the beauty of the new product, and the demand it triggered was high. This raised the wish of the discoverer, probably a farmer in Airolo or in Fontana, to remain in the exclusive possession of its sales and when one asked the specimen dealer Vizard in Berne through whom at that time the fossils from the Gotthardt were made popular where the new fossil came from, he would mention the Val Tremola as its birthplace. Thus the name tremolite was adopted, irrespective of the fact that no trace of the mineral exists in Val Tremola. However, the regions of the Gotthardt were soon explored more thoroughly; mineralogists scaled the cliffs of Campo Longo themselves; and tremolite was also found in other European localities."
Von Buch L. (1809): Der Gesellschaft naturforschender Freunde zu Berlin Magazin für die neuesten Entdeckungen in der gesammten Naturkunde, 3, p. 172

The above quote are taken from "The Early History of Tremolite" by Philippe Roth

Tremolite form the type locality origins from a silica rich triassic dolomite on the border between dolomite and quartz. This border zone rarely exceeds a thickness of 4 cm, but can be considerable larger parallell to the quartz. Cabinet sized specimens can consequently be found. Tremolite occurs both as crystal aggregates and single crystals.

Tremolite from Campolungo has, due to it's abundance in various museum collections, been used in numerous studies on amphiboles and the geological settings in which they occure.

Tremolite
Tanzania
Arusha Region, Lelatema Mts, Merelani Hills (Mererani)


Tremolite 5,7 cm	© Weinrich


Tremolite 2.8 cm tall	© vasco trancoso

The famous tanzanite mines of Merelani is also one of the world’s finest tremolite occurrences Although the location has been known by science since early in the 1960-ties, tremolite was not found here until 2005 when vanadium-rich (and probably chromium-rich) tremolite in single crystals to 2.8 cm, and jumbled groups of splintery tremolite crystals of a pearl-white to apple-green color were available at the 2006 Tucson Show. New finds in 2007 and onwards has led to a small and unsteady supply of new material, and several dealers offered crystals up to 3 cm in 2009.

Finely acicular crystals on tanzanite and heulandite have also been identified. The tremolite crystals all thought to be from Block D (see explanation below). The pale green Merelani tremolite crystals contain 0.32 weight percent V₂O₃ and probably trace amounts of Cr₂O₃ , which are thought to be the coloring agents. The deeper grass-green crystals probably contain moreCr₂O₃ . The tremolite shows a weak orange fluorescence under longwave ultraviolet light, and a moderate greenish yellow fluorescence under shortwave ultraviolet light.

The Merelani's tanzanite mines lie within 2 km wide by 8 km long field, first discovered by prospectors searching the steppe for anything of value. Small scale mining started in the 1960-ties, and has not been run as a large scale operation before the early 1990-ties. Mining started as a haphazard collection of small diggings and open pits in alluvium and bedrock but has expanded continuously into several major workings and many hundreds of small operations.

The Merelani mine today consists of four major parcels referred to as Block A, Block B, Block C and Block D, each exploiting veins that go successively deeper (from A to D). There are also several extensions, and the Machakecho workings, just to the west, where small-scale miners have exploited an alluvial deposit of tanzanite. Block A does not produce much, and today the majority of the production comes from block C, where a modern , hi-tech operation are run, producing between 1.5 and 2 million carats of tanzanite in 2009. Most collector-quality uncut crystals reaching the market are from the "native blocks" (Block B and Block D) where mining is conducted by hand, in a not so modern and highly dangerous operation.

The tremolite (and tanzanite) is found in metasedimentary rocks with a complex history of repeated metamorphic events. What originally started out as Al-rich calcareous, arenaceous and pelitic sediments was first metamorphosed to granulite facies at temperatures between 520 and 730 deg C and 7,7 to 9,1 Kbars, but later retrograde actions has formed kyanite-almandine rocks with beds of dolomitic and siliceous crystalline limestone. Bands of graphite gneiss, quartzo-feldspathic gneiss and kyanite gneiss are intercalated with the limestone. The gem material are formed by later crystallization in faults originated in the rocks, and vanadium and chromium leached from the metasediments has been incorporated in the minerals found in these faults, giving the strong and unusual color to the minerals. This recrystallization phase took place during the Mozambique Orogeny around 600 million years ago,

Literature:
Petrology and lithogeochemistry of the mineralized tanzanite-grossular bearings rocks in the Merelani-Lelatema area, northeastern Tanzania, Tanzania Journal of Science Vol 29 (2003) EP Malisa

The Merelani tanzanite mines: Lelatema Mountains, Arusha Region, Tanzania, The Mineralogical Record (sept 2009), Wilson, Wendell E.

Yellowish green diopside and tremolite from Merelani, Tanzania, Eric A. Fritz, Brendan M. Laurs, Robert T. Downs, and Gelu Costin

Tremolite
USA
Connecticut, Litchfield Co, Canaan, Falls Village, Canaan Lime Quarry (Redwing Quarry)


Tremolite in calcite 5 cm spray	© 2000 John H. Betts

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Tremolite
USA
New Jersey, Sussex Co., Franklin Mining District, Franklin,Franklin Quarry (Moses Bigelow Quarry; Farber Quarry)


Tremolite 3.5 cm

The Franklin mining district is host for 353 valid mineral species, and is the type locality of 68 of those. Several amphibole minerals are amongst these, tremolite therefore being one of many similar minerals, so label with caution.

Tremolite is a common accessory mineral in the Franklin Marble, which is a coarsely grained calcite marble, which is locally local dolomitic. Tremolite is rarely found in the calcium silicate units of the orebody ( actinolite is more common near the orebodies, in particular near franklinite).

Tremolite occurs as euhedral crystals in much of the Franklin Marble. The crystals may occationally reach 10 cm and more in length, and are associated with graphite, chondrodite, calcite, arsenopyrite, phlogopite, chlorite, and other species. The Franklin tremolite is colorless to white or gray, with vitreous luster. Analysed samples shows impurities of Mn,Zn and Fe, with some species intermediate in composition between actinolite (which is also present) and tremolite.

From time to time also pseudomorphs of diopside after tremolite, in which brightly-fluorescent diopside has replaced bladed crystals of tremolite can be found

Fibrous tremolite has also been identified on on slickensides with zincite , carbonates and serpentine

Fluortremolite
USA
New York, Orange Co., Pine Island, Atlas quarry

"Fluorotremolite (fig. 8) from the Atlas quarry occurs in long prismatic to acicular, transparent, colorless to pale gray crystals to 4 cm, in parallel growth with fluoro-edenite, or isolated in marble. Inclusions of graphite flakes oriented along the elongation of the crystals are common. The mineral fluoresces pale yellow with a greenish tint in longwave and strong yellow with greenish tints in shortwave ultraviolet radiation."

Marian Lupulescu (2008): Amphibole Group Minerals from New York State. Rocks & Minerals, Volum,e 83 May/June.

Tremolite
USA
New York, St Lawrence Co., Gouverneur, Reese Farm (Dale Bush Farm; Jones Farm)


Tremolite ~11cm wide	©


Tremolite & Uvite 8cm wide	©

The Reese Farm are more known for its tourmaline specimens, but excellent tremolite specimens and combo specimens have also been, and still can be found.

The Lawrence County of New York in the USA hosts a number of tremolite occurrences, Mindat lists 29 locations, and there are probably many more in the metasedimentary and metasomatic precambriam rocks formed in the Grenville orogony. The area is one of the classic sources of mineral specimens, shown by the following quote:

“No introduction to the minerals of the western Adirondack region in upper New York State need be given to any one interested in mineralogy. Good crystals from its many localities adorn nearly all mineral collections and most of the easily obtainable show specimens were taken long ago. There is still a great deal left, however, which will repay a trip into the region.”

The quote is taken from “The Minerals of St. Lawrence, Jefferson and Lewis Counties, New York.” By W.M.Agar, Princton University, 1921.

Unlike many other places, the tremolite found here is of particular interest for collectors. This is more than anything due to the manganese bearing variety hexagonite, showing a beautiful lavender color, thus automatically becoming more attractive. Hexagonite was at first interpreted as a mineral with hexagonal crystals, related to beryl, but this first assumption was firmly corrected by George A. Koexig Ph.D in a short paper published at the Philadelphia Academic Society in 1876:

“The appearance of the mineral is altogether novel and striking; the fine light amethystine color, and a peculiar lustre, together with the aggregative entwining of the crystals, renders it very attractive to the eye. My doubts as to the accuracy of Mr. Goldsmith's determination being roused, I resolved to examine the mineral myself, having
been furnished with plentiful material, through Mr. Clarence C.Bement's kindness, who was the first in this city to obtain it.”

As the title “Hexagonite, Goldsmith, a variety of tremolite” suggests, Dr Koexig it nailed it. He supports his conclusions by careful crystal measurements and chemical analysis, even to the detail where he attributes the pale lilac color to the small Mn Content.

The tremolite, together with other minerals formed by metamorphic reactions between the marble and quartzite. It is believed that some of the tremolite have later been altered to talc, anthofyllite and serpentine. This retrograde metamorphosis has been extensive to the level where talc has been and still is mined.

The colourless and white tremolite are predominantly found directly in the marble and large subhedral crystals to more than 50cm long and 15 cm thick can be found. Terminated, well formed crystals rarely exceeds 10cm.
The hexagonite variety is found in nearly mono-mineralic zones between the massive talc ore and
hanging wall dolomite, and the individual crystals are normally less than 1cm, but individual crystals exceeding 10 cm are known.

Tremolite
USA
New York, St Lawrence Co., West Pierrepont, Selleck Road Locality (Selleck Road tremolite locality)


Tremolite 4.5 cm tall	© 2001 John H. Betts

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Tremolite
USA
New York, St Lawrence Co., Balmat-Edwards Zinc District


Tremolite 10.8 cm crystal	© Rob Lavinsky

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Tremolite
USA
New York, St Lawrence Co., Fowler


Tremolite 2.7 cm	© Rob Lavinsky

Tremolite
USA
New York, St Lawrence Co., Fowler, Gouverneur Mine


Tremolite 11.45cm wide	© Jasun McAvoy


Tremolite, 2cm xl.	© Martins da Pedra


Tremolite 6.6cm wide	© Jasun McAvoy


Tremolite 3.62cm tall	© Jasun McAvoy

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Tungsten (8 replies)

Rob Woodside — Tue, 26 Oct 2010 00:18:48 +0000

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Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Below are some preliminary notes I have made about Tungsten. This entry and thread has been made as a place holder for information that you will hopefully contribute about Tungsten. It should be in no way be thought of as a claim I have staked out to write about this mineral, and in fact is an invitation for someone to step forward and create the article about this mineral. If you are so inclined and have questions about the format that such an article should have, go the The welcome topic at the top of the Best Minerals forum and read what has been posted there. Also take a look at some of the more mature articles that have already been written like Rhodochrosite, Adamite, Millerite etc. You will need also to pick out other images of Tungsten that will go into the article.

Tungsten
W Cubic


Bright grain of native Tungsten in back scattered electron image	© PMK

Tungsten Native Element and Rare Species Collections

Known only as a few specimens from the earth and the moon. Synthetic material is often sold as Native Tungsten by fraud artists. I met Victor Ivanovich Stepanov in 1987 and asked him about W in wolframite from Transbaikalia and he replied with a good thick Russian accent "Product of American technology!" It sticks out like a sore thumb under the elelectron microprobe.To complicate matters it shows up in heavy mineral alluvial concentrates. These sample a widespread geology and often pick up anthropogenic material. These days one often finds metallic titanium in them from fallen space junk. So many of the earlier reported occurences of Native Tungsten were highly suspect. Certainly two honest occurences are from the moon where it was observed as a micron sized grain and in the Subarctic Urals where it was first found in an alluvial concentrate and later in a quartz vein occurence that drained into the concentrates.

Tungsten
Moon
Mare Crisium, Luna 24 landing site

Scanning electron microscope image of the fragment of lunar silicate glass particle from coarse fraction of regolith. The bright grain is a native tungsten aggregate overgrown with a carboniferous film covering the glass. Associated minerals located near this grain (within about 30 μm circle) are native molybdenum, copper, nickel and chromium. Depth of sampling is about 86 cm from Moon surface. The specimen is in the collection of Lunar regolith belonging to IGEM RAS and Andrei V. Mokhov took the photo.

Pavel Kartashov writes:

What about the Moon, impact events are the great refinery - they evaporate cubic kms of rock dividing elements of rock each from other in plasma. So some of them hadn't enough time to oxidize back.

Tungsten
Earth
Russia
Urals Region, Subarctic Urals, Bol'shaya Pol'ya River

Pavel Kartashov writes:

"On Bol'shaya Pol'ya river was found large cm size nugget of native wolfram. It was found in borehole of gold placier from ~30 m depth. This layer of gravels was deposited 50000-100000 years ago. May it be product of Hiperborean culture? Or may be Atlanteans had visited this region?

This native W contained <<1 micrometer grains of cubic Y2O3. It was observed in TEM preparates and was investigated on ancient (70th issued) KEVEX attachment. It didn't allow to obtain complete REE spectrum from the particles. And on KEVEX spectra other than Y peaks were invisible. BUT yesterday I analysed Alpine "gadolinite" and on its ED spectra also minor REE were invisible. But quantitative analysis on modern equipment show composition (Y1.58REE.30)1.88 where REE were Nd,Sm,Gd,Tb,Dy,Er,Yb. So may be this Y oxide isn't too pure. But it is too small for to be investigated by our microprobe. I had made some microprobe preparates from material of this nugget, but was unable to detect Y oxide inclusions in it because they are to small.

My the second find of native W in the region confirming natural source of W nugget into placier of B. Pol'ya river. I had identify it in quartz wein #60 of Puiva Mt. It is remarcable, that Puiva Mt is located in headstream of Bol'shaya Pol'ya river So apparently exactly this region supply native W gold placiers of the river. Very important is the fact, that on Puiva Mt. was apparently exist big nugget of native W. Unfortunately it was crushed up to 0.3 mm fraction with small semiindustrial probe of quartz of 2 ton weight. I observe fragments of this individual in heavy concentrayes from this probe. In whole pan of this concentrate (mainly apatite) was presented about 30-50 g of W particles as I am suppose. Unfortunately I am not Victor Ivanovich and recognize these grey metallic grains as some arsenide or sulphoarsenide. I was EXTREMELY foolish and selected for microprobe identification only 3 grains. How I was surprised, when all 3 turned out metallic W. Unfortunately all pan of this heavy concentrate was already thrown out, when I'd return to lab to take it... "

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Thenardite (3 replies)

Rock Currier — Tue, 27 Oct 2009 10:17:58 +0000


Thenardite, Soda Lake, Carrizo Plain, San Luis Obispo Co., California, USA 10cm wide	©

Thenardite is a water soluble evaporate mineral and unless care is taken to keep these in a cool dry place, they will end up as piles of white powder in your storage boxes. Most of the localities where these specimens occur they can be found in great abundance and can be harvested hear after year and would be if the market could absorb them.
[Rock Currier 2009]

Thenardite
Chile
Tarapacá Region


©

Thenardite
Egypt
Western Desert, Wadi Natrun depression


Thenardite FOV 8cm wide	© Elmar Lackner

Thenardite
Spain
Castile-La Mancha, Toledo, Ocaña, Villarrubia de Santiago


Thenardite 3.5cm wide	© Martins da Pedra

Thenardite after Mirabilite
USA
California, Kern Co., Kramer District, Boron


Thenardite after mirabilite 6cm wide	© Rob Lavinsky


Thenardite after mirabilite 3.8cm wide	© Rob Lavinsky


Thenardite after Mirabilite 9cm tall	© Rob Lavinsky


Thenardite after mirabilite 6,4cm tall	© Rob Lavinsky


Thenardite after Mirabilite 7.8cm	© Rob Lavinsky


Thenardite after Mirabilite 9,6cm wide	© Rob Lavinsky

These attractive specimens did not form in the borate deposit at Boron, but rather in the settling ponds west of the refinery which is also situated west of the open pit mine that has produced almost all the specimens that have made this deposit familiar to collectors. At one time it was the largest underground operation in California with more than 200 miles of workings but the advent of large earth moving equipment made it more economical to mine the deposit as an open pit operation, though some day when the pit gets deep enough, mining may again shift to an underground operation if that will make it more profitable. When the ore is mined, and almost all the ore that is currently being exploited is crystalline Borax, it is crushed and run into big million gallon plus dissolving tanks. In these tanks it is mixed with hot water and large rotating mixing blades stir the borax till it is dissolved and the mud and impurities in the ore drops to the bottom of the tanks. Eventually this mud is pumped out into big shallow settling ponds where the mud settles out. Sometimes when the conditions are right in these ponds, especially in the early morning when the temperature is low, beautiful big crystals of mirabilite grow in the water where they can be harvested by interested parties. This does not mean the general public, because this is a big industrial operation and access to the mine and refinery areas is strictly controlled. These specimens were collected by Jim Minette who for years worked for US Borax as a mining engineer and eventually became general manager of the mining operation there. He would sometimes go out early in the morning to settling ponds and collect these specimens and lay them out on the bank to dry which didn't take very long. They Mirabilite would loose its water and convert to Thenardite. They had to be handled with great care because they were very delicate. He would take them home and spray them with Krylon plastic to preserve them.
[Rock Currier 2009]

Thenardite
USA
California, San Luis Obispo Co. Carrizo Plain, Soda Lake.


Thenardite 8.5cm wide	© Michael C. Roarke


Thenardite, 9cm wide	© Arliguie M


Thenardite 5.2cm wide	© JSS

Soda lake, a bit east of Taft, California is probably home to most of the thenardite specimens that have reached the mineral market during the last 30 years. They are typically clusters of diamond shaped crystals, but gray and unless kept in a cool dry environment have a nasty habit of ending up as piles of white crumbs in your collection, but I have some I collected twenty years ago that are still in good shape. These can still be collected today but collecting is best toward the end of hot dry summers when maximum evaporation has taken place on the lake bed. The lake is really a dry lake bed covered by salt, mostly halite and is many acres in extent and is thought to be a slump feature created by the great San Andreas fault that runs just to the west of the lake. The lake is seasonal and in late summer any water is usually long gone and one is presented with a flat pan of salt which on closer inspection consists of polygonal blocks of salt separated from each other by ridges of rough salt raised an inch or two above the smooth center of the polygons. To collect you walk out onto the surface of the lake perhaps 50 or 100 meters and pick a nice big polygon and break a hole down through the salt crust that is perhaps 20 cm thick to the mud below in which the thenardite crystals commonly grow. The margins of the lake are usually quite muddy and you can easily sink up to your hips in the mud unless you are careful in getting across this and onto the firmer salt. Some people lay down a piece of old plywood or some wooden planks. Some make up crude “snow shoes” like nailing an old pair of sneakers to pieces of wood. This distributes your weight evenly on the surface and keeps you from sinking in. Once you have broken through down into the mud layer you reach down into the mud with you hands and feel around for the crystals. You have to feel carefully because they can be quite sharp. You pull them out of the mud, rinse the mud off with the brine and lay them at the side of the hole and dive back in for more. You get single crystals and clusters, some of them so large you have to break them up a little to get them out of the hole. As the hole gets larger, the crust of the polygon starts to break up and you start to sink down a little. It helps if you take along a piece of plywood to lie on, but ultimately you get more and more of the often fowl smelling mud on you and pretty soon you are pretty well covered with the stuff. Pretty soon you just don’t care any more and late in the day if one of your collecting buddies has a nice clean spot, say on the back of his shirt, you are more likely than not to help him cover that spot with mud as well whether he wants you to or not. If you are lucky you may find some blödite crystals, though I was only able to find this elusive mineral one time and that was quite deep in the mud. Sometimes you pull fabulous crystal clusters of mirabilite from the mud as well and at least for a few minuites you think you have struck the mother load till they start to wilt and turn white and in the space of an hour or two turn into a pile of white crumbles on the side of your hole. See the article on mirabilite if you want to see what a good unaltered mirabilite looks like.

When you collect at this locality you really need to take along an extra set of clothing and about five gallons of water with which to wash off the mud when you finish collecting. I made the mistake first time around of not doing this, and it took me a week to wash out most of the mud. I used the last of my drinking water to wash the caked salt off of my arms. The caked salt also sort of welded all the hair on my arms together which gave one quite a strange sensation when you brushed up against something. Wow! That felt pretty strange. After you have removed your pants, they frequently will stand up on their own because of the caked salt and mud in them. This is one of the dirtiest collecting localities that I have ever experienced.
[Rock Currier 2009]

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Turquoise (37 replies)

Harjo Neutkens — Wed, 09 May 2012 19:15:31 +0000

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Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities? After each set of pictures there should be some descriptive text. If none appears it means that we need someone to tell us about the specimens from that locality and something about the geology of the occurrence. If a locality lacks a photograph we need someone to supply us with a photograph of a specimen from that locality. Thanks for your cooperation!

Turquoise
Cu(Al,Fe³⁺)₆[(OH)₄|(PO₄)₂]₂-4H₂O Triclinic


Turquoise from Ottre, Vielsalm Massif, Belgium	© Harjo

Turquoise is a typical mineral for Copper containing oxidation zones in Silica and Aluminium rich rocks. It forms even with low Copper content in cracks, faults and impregnation zones together with clay minerals, Aluminium silicates, and Aluminium hydroxides.
Turquoise often appears as mixtures of different members of a series, only after analysis one can conclude if it's pure Turquoise. Turquoise forms three series: Turquoise-Chalcosiderite, Turquoise-Aheylite-Planerite and Turquoise-Faustite.
Often there are other minerals present in Turquoise aggregates like Silica, Quartz, Kaolinite, Montmorillonite, Allophan and other Phosphates. More or less Iron rich varieties of Turquoise are "Henwoodite" and "Rasleighite".

Europeans came to know Turquoise in the middle ages through the crusades, probably the rocks were brought from the Sinai or Persia. The name most likely derives from Turkey because the stones from the Orient had to travel through Turkey before finally arriving in Europe.
Turquoise has been used as a gem and ornamental stone since a very long time. Already in 5500 b.c. the Turquoise from the Sinai peninsula was known and Mexico the stone was already known since 700 b.c.

The price for Turquoise varies according to the quality of the material. Factors that decide the price are for instance the size, texture, colour and locality. Some Turquoise from classic U.S. localities are quite expensive. Lander Blue is considered the most valuable of those (it is considered the most valuable Turquoise in the world), selling for prices around $165 per carat whereas most Turquoise sells for carat prices in the range of $1 to $10.

Nowadays Turquoise remains a sought after gem and ornamental stone so people have tried to imitate Turquoise, already in 1927 K Hoffmann succeeded in making synthetic Turquoise by mixing powders from Malachite, Aluminium hydroxide and concentrated phosphoric acid and compressing them at 100 degrees Celsius. In 1972 a better Turquoise synthesis was developed by the American Gilson company ("Gilson-Turquoise" ).
Also the colour of Turquoise is sometimes enhanced by applying blue ink or blue polymers.

"Turquenite", as used in lapidary and mineral trade since the 1970s is as an artificially-coloured blue variety of Howlite or Magnesite dyed to resemble Turquoise and sold as a gemstone, often as tumbled stones. It is not suitable for carving (usually) as the dye does not often penetrate deep into the stone.
Confusingly, since 2004 the name has also been used by an American company to denote any mineral that has been subject to a process that the manufacturers call the "Eljen Process" which claims to make soft stones such as Turquoise harder and have more vibrant colours than in their original untreated state. Unlike the original 'Turquenite', this 'Turquenite' is apparently suitable for carving and lapidary use.
The American company has applied for a US trademark for the name 'Turquenite', however it remains to be seen whether the prior-use of the name as a dyed howlite/magnesite material will prevent the trademark being granted.

Turquoise
Argentina
Córdoba, Punilla Department, Tanti, Cerro Blanco pegmatite District


Turquoise, 2x2cm	© Marcelo O Olsina


Turquoise, 3x1,5cm	© Martins da Pedra

Cerro Blanco is a hill with several pegmatite quarries on it, the most well-known being El Criollo, about 10km from the nearest town, Tanti (Punilla Dept.), in Cordoba Province.

Turquoise
Australia
South Australia, Eyre peninsula, Middleback Range, Iron Knob, Iron Monarch open cut


Turquoise FOV 3cm	© Richard Bayerl


Turquoise, 4,4x3cm	© JSS

An open pit iron mine (now abandoned), famous for a wealth of well-crystallised phosphates.
One of the rare localities where Turquoise can be found as single crystals.

Turquoise
Belgium
Luxembourg Province, Stavelot Massif, Vielsalm


Turquoise FOV 6x4cm	© JDehove


Turquoise, 6x3cm	© 2002 John H. Betts


Turquoise FOV 0,8cm	© Harjo


Turquoise FOV 0,6cm	© Harjo

The Stavelot Massif has a long mining history. The object of this mining activity was the so called Coticule, known since ages as an excellent abrasive stone for sharpening knives, razorblades and the likes. Coticule is a metamorphic rock consisting predominantly of very small Spessartine Garnets, it appears as narrow veins in slate. In the Coticule small Quartz veins appear and it is inside these and in small fissures in the Coticule (the so called "cresse" ) that the Turquoise crystallised along with an array of other minerals. The Turquoise appears as coatings on Quartz or Chlorite, globular aggregates and Vielsalm is also one of the few localities worldwide where Turquoise can be found as individual crystals.
No mining activity for Coticule remains in the Vielsalm area and most of the mines are inaccessible nowadays and some of the dumps have been recultivated or are now part of a national heritage site. It is however still possible to find the odd specimen of nice Turquoise. In the nearby village of Lierneux a mining engineer from the now closed coal mines of Limburg recently started a renewed mining effort for Coticule in a small Quarry, he now successfully markets his excellent abrasive stone as a luxury product worldwide.
[Harjo Neutkens 2009]

Turquoise
Belgium
Luxembourg Province, Stavelot Massif, Vielsalm, Ottré


Turquoise FOV 0,8cm	© Harjo


Turquoise FOV 0,8cm	© Harjo

Upper Salmian (Ordovician) Mn-rich metapelites (phyllades) (Hercynian metamorphism) on the south border of Stavelot Massif.
Turquoise was First discovered in Belgium near the small township of Ottré, van Wambeke mentions a find of Turquoise from Ottre in 1958 (Bull. Soc. Belge) Nowadays it is still possible to find excellent specimens of Turquoise in the still active Pagani quarry. The quarry works the slate for building material used for walls and roofs in traditional rustic houses. Several small veins of Coticule appear in the quarry in which the Turquoise can be found. Interesting is the find of Torbernite crystals completely covered by Turquoise. The quarry is private property so one should have permission from the owner to enter, however, the owner rarely gives permission to enter the quarry. Apart from the here mentioned localities of Vielsalm and Ottré there are three other localities in the Stavelot Massif where one can find Turquoise. These are Salm-Château, Bihain (the type locality of Vantasselite) and Lierneux.
[Harjo Neutkens 2009]

Turquoise
China
Hubei Province


Turquoise, 6,4x2,5cm	© Martin Patus


Turquoise, 3,8x3,3cm	© Safaa Yu

Turquoise has been mined in China since thousands of years, especially in Hubei province. There are three main Turquoise mining areas in Hubei. An important mine is Yungaisi mine (Yungaishi means "cloud covered temple" ), it has been worked since 1954 and produced massive Turquoise pieces up to 100 kg!
Since 1954 over 450 tons of Turquoise has been excavated in Yungaishi mine.

Turquoise
Democratic Republic of Congo
Katanga (Shaba), Katanga Copper Crescent, Western area, Kolwezi, Katonto hill


Spectacular Turquoise crystal specimen from Katonto hill, FOV5,2cm	© Paul De Bondt

Katonto is a hill situated north west of Kolwezi.
Some very fine Turquoise crystals, similar to those of Lynch Station in Virginia, where found. It hasn't been a prolific supplier of Turquoise but some remarkable specimens of Turquoise crystals justify Katonto hill featuring in a Turquoise article!
The locality is also known for its remarkable pseudomorphs of Limonite after Pyrite crystals and Quartz crystals.

Turquoise
Egypt
Sinai Peninsula, Wadi Maghara

Turquoise mining by Dynasty III ruler, Djoser Netjerikhet.

Turquoise
France
Auvergne, Allier, Ébreuil, Échassières


Turquoise FOV 0,1cm	© JM. Johannet


Turquoise FOV 0,3cm	© Chollet Pascal

Small but very beautiful micromounts of Turquoise crystals have come from the dumps of two veins, the Mazet vein and the Ste Barbe vein (the Montmins mine) that have been worked on during the active mining period in Échassières. They are early 20th century tungsten mines, working wolframite-bearing quartz veins hosted by micaceous slates and granite, famous for a wealth of well-crystallised secondary oxysalt minerals (mainly phosphates and arsenates).

Turquoise
France
Limousin, Creuse, Boussac, Montebras-en-Soumans, Montebras Mine


Turquoise, 6x4cm	© Arliguie M


Turquoise FOV 0,5cm	© P.Queneau

Located 1 km west of Montebras and around 7 km SE of Boussac, the best French locality for Turquoise. Larger specimens of massive Turquoise have been found as well as attractive micromounts with Turquoise crystals.

Turquoise
Iran
Khorasan (Khorassan; Khorasan va Sistan; Khurasan; Khorass; Khoras) Province, Ali-Mirsa-Kuh Mts, Nishâpûr (Nishabur; Neyshabur), Nishâpûr Deposit


Turquoise, 4cm	© Rui Nunes 2008

Arguably the worlds finest specimens of predominantly massive Turquoise have come from this deposit. Mined by the ancient Persians.
The most important mine in the region is the Abdurezza mine, a primary deposit excavated underground. Turquoise is encountered as fillings of up to 3 cm wide faults and cracks in the brecciated Trachyte host rock.
There are also secondary Turquoise deposits in the area where Turquoise weathered out of the host rock can be found.

Turquoise
Israel
Eilat


Turquoise, 7,4x4cm	© Marco Barsanti

Locality of so-called "Eilat stone", chrysocolla intergrown with turquoise and pseudomalachite. However, this occurrence has been completely worked out, and the "Eilat stone" currently sold to tourists in Israel is really from Morocco, Congo and Arizona. Supposedly the locality is the same as the legendary "King Solomon's mines". [Marco Barsanti]

Turquoise
Kazakhstan
Qaraghandy Oblysy (Karaganda Oblast'), Karkaralinsk Rayon, Karkaralinsk (Qarqaraly; Karsakpaj; Qarsaqpaj; Kaskelen)


Turquoise, 5x2,7cm	© JSS


Turquoise, 3,7x2,3cm	© JSS

Turquoise
Mexico
Baja California Norte, Mun. de Ensenada, El Aguajito


Turquoise, 2x1,4cm	© 2003 John H. Betts


Turquoise, 2x1,5cm	© 2003 John H. Betts

Locality for very goos cutting grade Turquoise. Further Turquoise prospects in the region are El Rosario, Laguna Chapala and Los Arrastos.

Turquoise
Mexico
Sonora


Turquoise ps. after Apatite 4,2x3,1cm	© Rob Lavinsky

Very interesting replacement pseudomorphs of Turquoise after Apatite can be found in several localities in Sonora, notably at Cumobabi, La Caridad, Nacozari de García and Cananea. The pseudomophosed crystals can get up to 3 cm large. The name of Cumobabi mine derives from Cu (Copper), Mo (Molybdenum) and babi, meaning "place" in the native language.

Turquoise
Portugal
Évora District, Vila Viçosa, Pardais, Miguel vacas Mine


Turquoise FOV 1,2cm	© Rui Nunes 2007


Turquoise FOV 1,5cm	© Rui Nunes 2005


Turquoise, Libethenite FOV 1,5cm	© Rui Nunes 2006


Turquoise FOV 3cm	© Rui Nunes 2007

Excellent specimens of Turquoise, sometimes attractively on Libethenite (famous for the locality) have been found in the brecciated Quartzite of the Miguel Vacas mine.

Turquoise
Republic of South Africa
Nothern Cape Province, Namaqualand


Turquoise after mammal bones 10,5x7,5cm	© Rob Lavinsky

Weather the bones of such fossils are actually replaced by Turquoise remains questionable. Several studies have been undertaken over the years. I'd like to refer to an excellent article on Mindat by Daniel Russell: "Odontolite" or "Bone Turquoise"

Turquoise
Spain
Castile and Leon, Zamora, Palazuelo de las Cuevas


Turquoise 3,8x3cm	© J.A.CENDON


Turquoise 2x1,7cm	© J.A.CENDON

Turquoise
United Kingdom
England, Cornwall, Liskeard District, Caradon & Phoenix Area (South-Eastern Bodmin Moor), Wheal Phoenix (Phoenix United Mine; West Phoenix Mine)


"Henwoodite" FOV 1cm	© De Nul, Richard


"Henwoodite", scale 1 Inch rule 1cm	©

Mining first commenced in 1836 under the name of Cornwall United Mine, but was unsuccessful. Reopened about 1844 as Phoenix Mine, West Phoenix Mine was included within the set in 1875, after which the mine was worked as Phoenix United.
Most of dumps removed at closure, including engine houses, but Prince of Wales Shaft has complex of buildings associated with it. The mine is famous for very good specimens of the Turquoise variety Henwoodite.

Turquoise
United Kingdom
England, Cornwall, St Austell District, Luxulyan Area (Luxulian Area), Hensbarrow Downs, Bugle, Bunny Mine (Bonny Mine; St Austell Hills Mine; Shelton Mine)


Turquoise, 5,5x4,5cm	© Rob Lavinsky


"Rashleighite" FOV 0,6cm	© Leon Hupperichs

Turquoise
United Kingdom
England, Cornwall, St Austell District, Luxulyan Area (Luxulian Area), Hensbarrow Downs, Stenalees, Gunheath China Clay Pit


Turquoise, 12x10cm	© 1


Turquoise, 15x10cm	© De Nul, Richard

Famous English locality for good Turquoise specimens. In the so called "Turquoise Lode" a near vertical vein in granite chunks of Turquoise of more then 10 cm large have been found. The Turquoise appears as massive chunks as well as pockets lined with very nice Turquoise crystals. Both Iron rich Turquoise varieties Henwoodite and Rashleighite also appear in the quarry.
Much of the green turquoise is assumed to be 'rashleighite' (ferroan turquoise) and may (especially at Phoenix) grade into Chalcosiderite as it gets darker. [Jolyon Ralph]

Turquoise
USA
Arizona, Cochise Co., Dragoon Mts, Turquoise District (Courtland-Gleeson District)

A Pb-Ag-Au-Cu-Zn-Mn-Quartzite-Turquoise mining district located in T.19, 20S., R.24, 25E. This District is located about 18 miles NE of Tombstone and 20 miles north of Bisbee. It occupies an area about 4 miles long from north to south by 2 miles wide in the southeastern margin of the Dragoon Mountains.

The principal features of relief are two ridges of NNW-ward trend, fringed on the east by low foothills. The northern, Turquoise Ridge, is separated from the southern, Gleeson Ridge, by a narrow gulch. These ridges are each about 2 miles long by less than a mile wide, and they rise 900 to 1,200 feet above the adjacent plains.
The structure at Gleeson and Courtland is highly complex due to faulting and igneous intrusions.
Quartz monzonite and quartz-monzonite porphyry intrude the Paleozoic and older rocks but were not found affecting the Cretaceous. Granite and felsite cut the monzonites, and the granite invades the Cretaceous beds.
The strata of Turquoise and Gleeson ridges predominantly strike between N. and N30ºE., and dip steeply eastward, but locally they show considerable variations in altitude.
Steeply dipping faults of general northerly and easterly trends are common in the district. Movement on them has been both vertical and horizontal, and locally they displace the low-angle faults.

Mineralization is of several types: (1) Copper carbonates and oxides in irregular blanket deposits where Cambrian Bolsa Quartzite and Abrigo Limestone are thrusted over Carboniferous limestone; copper sulfides, oxides, and carbonates in irregular replacement deposits in Cambrian Abrigo Limestone; and copper sulfides, oxides and carbonates in irregular, tabular, pyritic lenses in Carboniferous limestone along, or close to, a contact with quartz monzonite intrusive; (2) Lead and zinc carbonates, lead sulphate, and zinc silicate with silver chloride, manganese and minor copper and gold in irregular orebodies in Pennsylvanian-Permian Naco Group limestones along, and at intersections of, fractures and faults; (3) Turquoise in near-surface stringers and lenses in altered granite and quartzite; (4) Manganese oxides in irregular bunches, lenses and masses along fractures in limestone; and (5) Spotty and weak base metal ores with gold and silver values in veins in intrusive rocks.
Workings include numerous mines and prospects developed by shafts, tunnels and adits since 1883. At least 887,000 tons of base metal ore and some 250 tons of manganese ore were produced plus some turquoise and a considerable production of quartzite smelter flux.

Turquoise
USA
Arizona, Gila Co., Globe-Miami District, Miami-Inspiration District, Miami, Sleeping Beauty Peak, Copper Cities Mine area, Copper Cities Mine (Sleeping Beauty Mine; Lost Gulch Mine; Yellow Metal Mine; Diamond-H Mine)


Turquoise, 8x7cm	© 2002 John H. Betts


Turquoise, 3,5x3,5cm	© 2002 John H. Betts

One of the foremost Turquoise localities in the USA.
A former surface and underground Cu-Mo-Ag-Au-gemstone-Zn-U-Pb mine located on the south flank of Sleeping Beauty Peak, 3½ miles north of Miami, straddling the middle part of the common boundary between the Globe and Inspiration quadrangles. Discovered 1896 and produced 1896-1982. Additional names which apply to this property: Porphyry Reserves.
Gold mining here started in 1896 by the Girard Mining Co. (Lost Gulch Mining Co. later). The Lost Gulch United Mines Co. was organized in 1909 to operate the properties of the Lost Gulch Mining Co.; reorganized as the Louis d-Or Gold Mining Co. in 1912 that worked the Bonanza, Badger & Cedar Tree claims for Au-Ag-Pb. About 1913 the Baldwin Syndicate of Chicago dispatched Charles E. Hart to examine these gold deposits. He concluded that a porphyry copper deposit was involved. The firm was reorganized as the Louis d'Or Mining and Milling Co. The Gila Monster, Bessie, and Sarah groups of claims covering the porphyry outcrops were optioned from J.W. Bennet. Exploration drilling began in 1917 and exploration continued until 1922 when the Louis d'Or shaft was sunk to the 360 level. The Bradley group of 5 patented claims was acquired in February, 1923. The company became insolvent in 1928 and the noteholders formed a new company jointly with the Pinto Valley Co., which was the Porphyry Reserve Copper Co. The company defaulted on bond interest payments in 1934. Copper Cities Mining Co., a new subsidiary iof the Miami Copper Co., purchased the surviving claims at sheriff's auction. Systematic exploration commenced in 1943 and was completed in 1948, confirming the extent of the orebody.
Mineralization is a porphyry copper deposit. Ore concentration was secondary enrichment. Alteration included quartz-sericite, argillic and weak propylitic processes.
This deposit is in a body of Lost Gulch quartz monzonite that has been intruded by several smaller bodies of granite porphyry. The outcrop of this quartz monzonite is a northeastward-trending horst block that is bounded on three sides by faults, the Sleeping Beauty fault on the NW side, the Ben Hur fault on the NE side, and the Miami fault on the east side. The south boundary of the mass is a steep intrusive contact with Pinal schist and the various rocks of the lower Precambrian dioritic complex.
The structures that are most important in their relation to the orebody are the Coronado and Drummond fault zones, which limit the copper orebody on the west and east sides, respectively.
The Coronado fault which strikes north and dips steeply west for a distance of 2,000 feet along the west side of the orebody, is a sheared, brecciated, and silicified zone, 100 to 300 feet wide. At the north and south ends of this broad part, the zone, trends westward and, in a distance of a few hundred feet, appears to contract to such a minor fissure that its outcrop is scarcely recognizable, but mining has exposed a strong gouge zone extending to the Sleeping Beauty fault. Where the fault zone is widest and most prominent, it is the boundary between the two facies of the quartz monzonite, the porphyritic quartz monzonite on the east, or footwall side, and the quartz monzonite porphyry on the west side. Small lenticular bodies of fine-grained diabase have been intruded along the fault zone.
The Drummond fault zone is much less prominent than the Coronado, but in other respects they are similar. The outcrop is a narrow zone of silicified breccia generally less than 25 feet wide. It strikes N.45ºW. and dips 60ºNE. It similarly forms the boundary between the two facies of the quartz monzonite along most of its recognizable length. Northeast of the Drummond fault zone, the quartz monzonite is traversed by many faults that strike north to NW and dip 50ºE. to vertical. Most of these faults are older than the diabase, and many of them have thin, discontinuous stringers or small irregular bodies of diabase intruded along them, particularly at the intersection of faults.
The mineralized quartz monzonite is intricately dissected by joints, fractures, and minor faults, some older and some younger than the period of mineralization. The older, or premineralization, fractures are now occupied by quartz-pyrite and chalcopyrite veinlets.

The Sleeping Beauty turquoise mine is located in Globe, Arizona. It derives its name from the Sleeping Beauty Mountain in the area and at one time was part of the Copper Cities copper operation. The mine produces a uniform light to medium blue turquoise. Because of its uniformity it has been a favorite of the Zuni Pueblo. Silversmiths there often use it in inlay, petit point and needlepoint, and matched jewellery sets.
The Sleeping Beauty mine has been one of the larger producers of turquoise in the country, although today less good turquoise is being produced than in the passed.
Sleeping Beauty has never been considered a hard turquoise and it has never been talked about in that same sense as many of the classic Nevada mines. But its beautiful clear blue colors mirror the blues of the sky and makes Sleeping Beauty, in every sense of the word, a true "Skystone." [Nevada Gem]

Turquoise
USA
California, San Bernardino Co., Turquoise Mountain District, Turquoise Mountain, Apache Canyon Mines


Turquoise-Beryl 2x1,1cm	© 2002 John H. Betts


Turquoise-Beryl 2,5x1,5cm	© 2002 John H. Betts

Locality for very interesting and nice replacement pseudomorphs of Turquoise after Beryl. Although there is a debate about whether the original mineral actually was Beryl, see the remark by Keith Wood below:

I am very skeptical of the turquoise ps beryl from California. To my knowledge they have been billed as such but never has any evidence been provided that the pseudomorphs actually use to be beryl. After looking at many specimens I think they are ps of apatite. This is based on the obvious chemical relationship between the minerals but more importantly on the crystallography of the better preserved examples. The most common pyramid face on beryl crystals is the [111-1] face. These are not seen on the specimens from california. Instead the [11-1-1] face is sometimes seen. This is a common face on apatites but less so beryl. (Pardon me if my Miller indices are messed up - it has been a long time.)
To explain what I mean about the crystal faces I'll add this. In beryl, there is commonly a face beveling the edge of the pinacoid between two hexagonal prism faces. That is, at the intersection of two prism faces and the pinacoid. These are not observed on the turquoise pseudos. In their simplest manifestations, when not complicated by adjacent pyramid faces, these faces form triangles.
On apatite, the most common pyramid face occurs at the intersection of one prism face and the pinacoid. these are the faces that I have seen on the psuedos. In their simplest manifestations, when not complicated by adjacent pyramid faces, these faces form trapezoids.While it is true a similar face sometimes occurs in beryl, it almost never occurs without the more common kind I described above.
Thus both the chemical relationship and crystallographic evidence point toward apatite as the original crystalline phase. [Keith Wood]

Turquoise
USA
Nevada, Clarck Co., Potosi Mountain area


Turquoise after fossil 5,7x5,3cm	© Rob Lavinsky

Weather the bones of such fossils are actually replaced by Turquoise remains questionable. Several studies have been undertaken over the years. I'd like to refer to an excellent article on Mindat by Daniel Russell: "Odontolite" or "Bone Turquoise"

Turquoise
USA
Nevada, Humboldt Co., Iron Point District, Valmy, Silver Coin Mine


Turquoise FOV 0,3cm	© Stephan Wolfsried


Turquoise FOV 0,3cm	© P Le Roch

Excellent locality for Turquoise crystals.

Turquoise
USA
Nevada, Lander Co.


Turquoise, 3,5cm	© 2003 John H. Betts


Turquoise, 3cm	© 2003 John H. Betts

Several mines in the area, notably the Fox mine and the White horse mine, produce nice Turquoise specimens.
The famous "Lander Blue" is considered the most valuable Turquoise in the world.

The Fox mine, once known as the Cortez, has been one of the largest producing mines in Nevada for almost a century. An official notice of location on the property under the name of "Fox Lode Mining Claim" was filed in 1914 by Charles Schmidtlein and Johnnie Francis. It had been mined in prehistoric times and had been known for years to the Indians of the area before the filed claim. The Fox mine is located in Lander County near Crescent Valley, Nevada. After going through numerous owners the mine was purchased in the 1940’s by Dowell Ward who continued the Fox’s development into Nevada’s most productive mine.
The Fox mine is said to have produced more turquoise than all other mines in Nevada put together. With at least 500,000 pounds mined by 1968 and for years producing more than 2,000 pounds per month. The mining operation continued to produce turquoise in quantity after 1968 and is still producing today. Fox turquoise is quite hard and runs from shades of green to an aqua blue color. It is found as both nuggets and vein material. [Nevada Gem]

On the south range of Bald Mountain in Lander County, Nevada is the Indian Mountain turquoise mine. A Shoshone sheepherder was said to have found the mine in 1970. The Indian Mountain was owned and operated by Ed Mauzy and J.W. Edgar, both legends in Nevada turquoise mining. Mining at Indian Mountain was carried on from late May to early October with a recovery of "about three pounds" (Turquoise Annual) of good turquoise a day. During winter the mine could be covered in up to 10 feet of snow. Indian Mountain turquoise was difficult to mine, found in very compact rock. During mining season the miners lived in trailers 75 miles from electricity and the closest telephone. The vein material and small nuggets found were of a very high grade turquoise. Seen in both a green and fine blue color, sometimes combined. The spider web Indian Mountain is considered to be some of the finer turquoise available. [Nevada Gem]

The Lander Blue turquoise mine in Lander County, Nevada is located between Battle Mountain and Tenabo. Found in 1973 it produced some of the most beautiful spider-webbed turquoise ever discovered. Today it is considered the most valuable turquoise known. Not surprisingly as early as 1975 it had been stated that Lander Blue “has become some of the most valued turquoise today.”
Like a number of the other high-grade strikes, Lander Blue was a very rich pocket discovery, and has been referred to as a “hat mine,” a term used to described small floats of turquoise because they could be “covered with a hat.” There were no extensive zones or long veins. These pockets are not uncommon in nature and once mined out they are gone forever. Lander Blue is almost entirely spider-webbed turquoise with colours from medium to deep blue and a black contrasting matrix. Although some other grades were found only approximately 100 pounds of the beautiful spider-web turquoise was mined.
Rita Hapgood, a one time blackjack dealer in Battle Mountain, while walking with her two sisters found little nuggets on the ground along Indian Creek in the Crescent Valley area of Nevada. After discovering this deposit of high-grade turquoise she went on to claim the site as the Mary Louise Lode Mining Claim, the name Mary Louise belonging to her mother. The mine bordered the Lander Ranch. Later the claim was sold to Marvin Syme and Henry 'Hank' Dorian for the sum of $10,000.00. They brought in Bob Johnson, who provided equipment and began working the claim. The three then named the company the Lander Blue Turquoise Corporation.
Marvin Syme ended up owning a number of turquoise mines in Nevada and later retired to Idaho. Hank Dorian operated the Nevada Club in Battle Mountain for a number of years until his passing and Bob and Dixie Johnson continued to sell Lander Blue turquoise until it ran out.The Lander Blue mine later became part of Lander Blue CabDowell Ward’s large string of mines (now belonging to Mrs. Ward).
Today, because of its rarity and value, there seems to be more Lander Blue for sale than was ever mined. With very little provenance available when buying beautiful Lander Blue, this material has truly become a case of ”Buyer Beware.” [Nevada Gem]

Turquoise
USA
Nevada, Esmeralda Co.

The Lone Mountain turquoise mine is located in Esmeralda County, Nevada, not far from Tonopah. It has been one of the great producers of Nevada turquoise. The colour ranges from a beautiful clear blue to a dark blue spider web. Lone Mountain has always been noted for holding its colour. To this day jewellery can be found that was made in the 1930’s or 1940’s with Lone Mountain turquoise just as blue as when it was made.
he mine was claimed by Lee Hand in 1920 first as the Blue Jay Mining Lode and later, after seeing that so many mines had been named Blue Jay, Hand changed the mine’s name to Lone Mountain. In 1927 at a depth of about 40 feet Bert Kopenhaver, who had leased the mine from Hand, found the beautiful spider web turquoise material that made Lone Mountain one of the top mines in the South west. Today, Lone Mountain’s beautiful blue spider web still gives Lander Blue, the most valuable turquoise in the world, a run for its money. The mine has continued to change hands over the years and even now a small amount of good material is being produced.
Another rare occurrence has been the "fossil turquoise" found in this mine. Plant fossils and sometimes seashells that have dissolved away leaving only the cavities were filled with turquoise deposits. Turquoise nuggets in moss agate have also been found.

The Royal Blue mine constituted the main workings in the area. The blue colors from this mine were beautiful and equal to any and the matrix was especially fine. In 1968 high-grade cut stones retailed at $1.00 a carat, which in today market would be the equivalent to over $20.00 a carat. The mine was discovered in 1902 by two miners named Workman and Davis, they later sold the mine for $3000. Over the years as with other mines the Royal Blue changed hands numerous times. The Bunker Hill mine was discovered in 1927 by Roy Palfreyman and Bert Kopenhaver. The Oscar Wehrend mine was discovered in 1909, production from this mine was low and not of the quality of the other two. Today the Royston district is still producing turquoise of high quality, but in limited amounts. [Nevada Gem]

Turquoise
USA
Nevada, Eureka Co., Lynn District, Number Eight mine (Blue Star mine)

The Number 8 turquoise mine is in the Lynn mining district in Eureka County, Nevada. The mine is considered depleted and has not produced turquoise for a number of years, although much is still available through collections and other holdings. Earl Buffington and Lawrence Springer filed the first formal claim on the property in 1929. Not long after that time the mine began going though a number of owners which included; Ted Johnson, Doc Wilson, Myron Clark, Lee Hand, the Edgar brother and Dowell Ward. All are important names in Nevada’s turquoise mining history. In 1950 the Edgars with a bulldozer began looking for copper. What they did uncover was a deposit of some of the finest spider web turquoise ever found in Nevada. The pocket produced more than 1,600 pounds of the very highest-grade turquoise, a discovery that is still being talked about today.
The colour of Number 8 varies from light blue, blue with shades of green to beautiful dark blue. It is found with a black, golden, red or brown matrix. With the black and red spider webbing being the most valued. Besides its beautiful turquoise, Number 8 has also been known for the large nuggets the mine produced. One nodule of high-grade turquoise that was sold to C.G. Wallace weighed more than nine pounds. Another uncovered was one of the largest turquoise nodules ever found. On June 23, 1954, T.G. Edgar, J.M. Edgar and Marvin Symes discovered a specimen that weighed 150 pounds. It was of good colour and hardness and classified as gem quality.
Today Number 8 turquoise is one of the most valuable stones that can be collected and one of the most beautiful that can be used in jewellery. High-grade Number 8 turquoise is by far some of the finest turquoise to ever have come out of Nevada. [Nevada Gem]

Turquoise
USA
New Mexico, Santa Fe Co., Cerrillos District, Los Cerrillos Mts., Tiffany Mines

The Cerrillos mining district has been called the earliest and the most important turquoise mining area in the country, already prehistoric mining existed around 800AD. It is located in Santa Fe County in north central New Mexico between the towns of Santa Fe and Albuquerque.
Turquoise there has been found in most every colour, it is hard and can be of very good quality. Today Cerrillos turquoise is considered rare and little is seen. It can still be found in jewellery where small claim owners and rock hounds have supplied the turquoise.
Pueblo miners had worked the area for centuries before the Spanish arrived. Over two hundred dig sites have been located. The main mining areas are located about three miles apart. One area is situated on Turquoise Hill and includes the Tiffany and Castilian mines.
Both the Tiffany and the Castilian were famous for their beautiful blue turquoise. Which was said to have been "as beautiful and of as good quality as Persian turquoise." The second area, located in the Cerrillos Hills, is Mount Chalchihuitl. It was the most extensive mining area and the largest prehistoric turquoise operation known on the American continent. For the complete history on the Cerrillos's mines see, Bennett's "Turquoise and the Indian" and Pogue's "Turquoise." [Nevada Gem]

Turquoise
USA
New Mexico, Grant Co., Burro Mountains District, Tyrone Area, Azure Mine

Hachita turquoise is from a group of mines near Old Hachita, Grant County, New Mexico. They include the Azure, Cameo, Galilee, and Aztec claims. The name "Hachita" comes from the Spanish term for "Little Hatchet". The small town itself was located in the foothills of the Little Hatchet Mountains in the Hachita Valley of New Mexico. The turquoise deposits lie in a location known as Turquoise Mountain about 6 mile west of the town.
Mined intensely in prehistoric times, settlers first came to the area when stories told by Indians mentioned turquoise deposits found in the hills of the Little Hatchet Mountains. Prospectors began working deposits around 1880’s and not only found the turquoise, but silver, copper, and gold as well. Many of the turquoise tunnels found were so ancient and carefully refilled by the Indians that they were only found by later mining. Some were said to have become so hard that the material had to be blasted loose.
These were hard mines to work with the nearest settlement of any size a few hundred miles away and the harsh furnace like conditions of the desert. Much of the first turquoise found was a hard fine pure-blue color. Today the Hachita turquoise seen in the market place is predominantly green with a light to dark brown matrix. Sometimes forming a beautiful spider webbing. [Nevada Gem]

Turquoise
USA
Virginia, Campbell Co., James River-Roanoke River Manganese District, Lynch Station, Bishop Mine


Turquoise, 2,8x2,4cm	© 2003 John H. Betts


Turquoise, 3,1x3,1cm	© Rob Lavinsky


Turquoise, 4,7x2,3cm	© Rob Lavinsky


Turquoise, 4,5x3cm	© 2002 John H. Betts


Turquoise FOV 0,1cm	© Saul Krotki 2004


Turquoise FOV 0,2cm	© Saul Krotki 2004

Arguably the most impostant locality for Turquoise crystals in the world, already described by the mineralogist W.T. Shaller in 1912. Specimens of occasionally notable size can be covered with up to 0,2 cm large Turquoise crystals.

Turquoise
Uzbekistan
Kyzylkum Desert, Central Kyzylkum Region, Auminzatau Mts


Turquoise, 7x4cm	© Pavel M. Kartashov


Turquoise, 5x3,5cm	© Pavel M. Kartashov

Literature on Turquoise

- Extra Lapis No. 16: Türkis, Der Edelstein mit der Farbe des Himmels, Stefan Weiss et al 1999, ISBN 3-921656-48-6
-The allure of Turquoise, Mark Nohl et al
-Turquoise Unearthed: An Illustrated Guide, Joe Dan Lowry and Joe P. Lowry
- Les gisements minéraux du Salmien dans le Massif de Stavelot, Michel Blondieau 2005
- Description des espèces minérales présentes dans les gisements salmiens du Massif de Stavelot, Michel Blondieu 2008

Internet resources on Turquoise

- Wikipedia
- The Turquoise Guide
- Miguel Vacas mine, Strahlen.org
- Wheal Phoenix
- Sleeping Beauty mine
- Tuquoise Museum
- Nevada Gem
- "Odontolite" or "Bone Turquoise" by Daniel Russell, Mindat

Work in Progress.......

[Harjo Neutkens 2009]

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Tincalconite (2 replies)

Rock Currier — Tue, 30 Jun 2009 10:40:12 +0000


1.Tincalconite after Borax, Boron, California ~15cm wide	©

Almost all Tincalconite specimens are pseudomorphs after Borax. They are water soluble. They are almost all a uniform opaque white color and if kept in conditions of fluctuating temperature and humidity have a nasty habit of ending up as piles of white powder. Some of the specimens, especially the ones from Boron, California make striking specimens, but will degrade unless cared for rigorously. Individual specimens to 30 cm are known, but these are very prone to cracking as the Borax dehydrates. Tincalconite crystals or rather their pseudomorphs after Borax are found where ever Borax crystallizes. Almost all the specimens that are in collections today are from altered Borax specimens that have been collected from the sumps and the bottoms of flooded stopes in the old underground mine at Boron. Some would argue that they are not real minerals because man had a hand in creating them and would not have formed at all except in artificial pools and ponds created by man. Some primary crystals of Tincalconite are known but those that I know of grew as somewhat elevated temperatures in the giant solution tanks at the borate refinery at Boron, California. About the only way to preserve these specimens is to keep them in a cool dry place that is free from humidity and temperature fluctuation and in some some sort of container to prevent dust, and exposure to atmospheric containments. In practical terms, that means that most storage facilities, institutional and private, can not care properly for these specimens.
[Rock Currier 2009]

Tincalconite
China
Tibet Autonomous Region


2.Tincalconite after Borax, Two ~1 inch crystals	©

These old specimens are in the collection of the British Museum of Natural history, are very fragile and show signs of falling apart because of partial rehydration and drying over the years. I am surprised that they have lasted as long as they have. When Borax is freshly altered to Tincalconite, the crystals are quite sharp like in picture one. After some years of alternating hydration and drying the crystals get a "puffy" look like we see in these Tibetan crystals in picture 2 above. We need someone to tell us about the Borax and Tincalconite production from Tibet.
[Rock Currier 2009]

Tincalconite
USA
California, Kern Co., Kramer District, Boron, U.S. Borax Open Pit Mine


3.Tincalconite after Borax about 12 cm wide	©


4.Tincalconite altering from Borax ~7cm wide	©


5.Tincalconite after Borax ~7cm wide	©


6.Tincalconite ~5cm wide	©

Most of the Tincalconite specimens from Boron have their origin as clusters of Borax crystals that have been collected from sumps and partially flooded stopes from the old underground mine. Most of them have been collected from the West Baker mine because for years it was possible to drive a vehicle through the big tunnels right to the partially flooded stopes where the collecting was done. This I think is still possible. At one time it used to be possible to drive from the West Baker mine over to the Baker mine which accessed the eastern part of the borate deposit, but I think that some breakdown from caving has closed this to vehicles. The specimen #1 is from the West Baker section of the mine and number four is from a sump in the older Baker mine. I am not sure exactly where the other Boron specimen are from exactly. At any rate, they are all from the old underground section of the mine which is no longer operated and not from the big new open pit mine that is now mined exclusively for ore. When the specimens are fresh, very white and sharp they can make spectacular specimens. Some have been traded with museums for very valuable specimens to curators who were not aware that these fine looking specimens would in years to come get dirty and subject to rehydration. Being water soluble you of course can not clean them with water. The "primary" Tincalconite in picture #6 was taken from one of the giant dissolving tanks in the refinery during one of their infrequent "clean outs" when they break open the side of these big round concrete structures so they can drive a bulldozer inside to clean things out. Primary Tincalconite and Kernite crystals have been found growing on the big rotating mixing blades and the walls of the tanks.
[Rock Currier 2009]

Tincalconite
USA
California San Bernardino Co., Searles Lake


Tincalconite after Borax on Hankiste ~8cm wide	© Rob Lavinsky

Searles Lake is a dry lake of some depth and is really nothing more than a big mash of brine and crystals of various water soluble minerals. Some of them are unique to the lake. Almost all of them are unstable to some degree and require special methods to keep them intact. A lot of halite (salt) crystals have been collected from ponds and trenches created by old mining projects in the lake bed but most of the other minerals are produced from bore holes down through the lake (crystal mash) and taken from drill cores or more commonly boosted to the surface by air bubbles that raft the crystals up to the surface where they spill out onto the hardened dry salt surface. Once a year, at the time of the local gem and mineral show the mining company that mines the lake for various chemicals lead field trips for collectors out onto the surface of the lake. They drop an explosive charge to the bottom of some of their bore holes (wells) and use air to raft the broken up crystal mash to the surface where collectors wait to pounce on them and load as many kilograms as possible into their cars, which they can drive right up to the collecting sites. The specimen of Hanksite pictured above was undoubtedly collected at one of these annual field trips. However, when the specimen was collected, the Tincalconite that is perched on the doubly terminated Hanksite was undoubtedly a relatively sharp, transparent Borax crystal which has since altered to Tincalconite and because of subsequent intermittent rehydration and drying started to loose its sharp crystal outline and get "puffy".
[Rock Currier 2009]

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Tunellite (no replies)

Rock Currier — Mon, 29 Jun 2009 07:34:32 +0000


1.Tunellite crystal ~8cm wide	©

By far the finest crystals of Tunellite yet found are from Boron, California. One of the best and largest know in pictured above. Larger crystals have been found, but they tend to be rather complex and do not have good crystal shapes like the one pictured above. Some of these complex crystals are up to about 15 cm in diameter but do their complex nature it is difficult to say if they are all part of the same crystal. Typically these complex Tunellite crystals are associated with Ulexite. Tunellite is one of the more stable borates, and unlike Colemanite and Ulexite crystals of Tunellite seem to retain their luster over long periods of time. Tunellite has been found at a number of other localities including localities in 'Turkey and Argentina and has been sparingly found in the Corkscrew mine in Death Valley, but the specimens are rather nondescript. We do not have any information about the Tunellite specimens that have been found in Turkey.
[Rock Currier 2009]

Tunellite
USA
California, Inyo Co., Boraxo Mine (Kern Borate; Boraxo Deposit; Boraxo No. 1 and No. 2; Clara Claim; Thompson Mine; Tenneco Mine)


2.Tunellite ~8cm wide	©

Very little Tunellite was found at this locality. Probably fewer than a flat full of specimens and this may be the best one. The mine is much better know for its wonderful big white shiny blocky Colemanite crystals and its fine specimens of Hydroboracite. Notice the color of the "mud/dirt/matrix in this Tunellite specimen and compare it to the color of the mud/dirt/matrix from the specimens from Boron below. You can usually identify the specimens from Boron by the distinctive color of the "mud" on its specimens.

Tunellite
USA
California, Kern Co., Kramer District, Boron, U.S. Borax Open Pit Mine


3.Tunellite crystals in mud, ~15cm wide	©


4.Tunellite & Ulexite ~11cm wide	©


5.Tunellite & minor Ulexite ~10cm wide	©


6.Tunellite on Ulexite ~7cm wide	©


7.Tunellite in mud ~4cm tall	©


8.Tunellite & Ulexite ~5cm across	© Peter Kohorst


9.Tunellite in Hydroboracite FOV 1.8cm	© Elmar Lackner

The best Tunellite crystals were found in the early days of the open pit mine (late 1950s) when a group of mineral collectors, members of a Los Angeles, California mineral club were collecting on the dump. One of them noticed some attractive well formed shiny white crystals in some of the distinct blue/green/tan mud that had been dumped by one of the big mine haul trucks. Soon they were all collecting specimens as fast as they could find them. Probably two or three hundred well formed crystals were collected. Almost all of them were removed from the mud like matrix. Perhaps the best and perhaps the only surviving specimens with the original distinctive Boron mud matrix is shown in picture#3 above. Over the years other kinds of Tunellite specimens have been found at boron, but they have always been rather rare.

Most of the Tunellite specimens show somewhat complex crystals associated with Ulexite as exampled by pictures 4, 5, & 8 above. Some of the specimens can be as much as a foot across with bulk of the specimen being the typical intergrown fibrous Ulexite almost always somewhat discolored by the mud that is everywhere present in the deposit. It is not really mud till you get it wet, but you get the picture I think. A particularly rare form of Tunellite are the bright shiny crystals that are found on Ulexite. See picture 6 above. More accurately they are found growing in among needles of acicular Ulexite and are exposed by brushing away the needles of Ulexite. Probably fewer than twenty of these specimens exist. Another type of Tunellite specimen was found at Boron during the early days and these were little flat blade like crystals of Tunellite like the ones in picture #9. These were associated with sharp micro needles of Hydroboracite. The crystals never got larger than about 5mm, but some specimens showed nice shiny white crystals of Tunellite and Hydroboracite. The one pictured above looks like it has never had a bath, and the Hydroboracite at the base of the Tunellite crystals is dirty form the ever present Boron "mud". Much finer specimens of this type exist and we will hopefully eventually be able to scare up a good picture of one to include in this article.
[Rock Currier 2009]

Here is a description by the mine geologist Joe Siefke of the last good find of Tunellite specimens at Boron: The last significant Tunellites I'm aware of was a hanging wall occurrence of tunellite. It was a chance find of my own in October, 1998. I was doing map recon near the toe of the massive 1997-98 pit north wall slope failure (35 million tons) when I came upon some vitreous cleavage flakes of tunellite. After that encounter I paid many lunchtime visits to the site (pick, shovel, bars, hammers, boxes, newspapers - you know the drill!). Over a couple of months I accumulated a few hundred specimens of mostly single crystals of roughly spherical shape ranging in size from 1/2 to 4 inches. Some are attached to ulexite; most were floaters in claystone. They appear to have formed in the recesses of the knobby top surface of a thick ulexite bed and arranged along a north-south structure for perhaps 150 feet length by 50 feet width. It was fun while it lasted.

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Re: Thortveitite (4 replies)

Olav Revheim — Mon, 26 Mar 2012 18:42:14 +0000


Kåbuland, Iveland, Aust-Agder, Norway. A 4cm xl.of on matrix	© Knut Eldjarn

Thortveitite is a member of the thortveitite-group of minerals, with a typical formula of (REE)₂[Si ₂ O₇. Thortveitite was the first mineral described with scandium as a main constituent in the formula, and it is still the most frequently found scandium mineral. It is however a rare mineral, and only a few localities have produced crystals of any size. Including the Y-free variety befanamite, little more than 100kgs of the mineral has been found, most of it from the Evje/iveland district in Norway and the Befanano pegmatite in Madagascar. The locations at Evje/Iveland has produced the largest crystals to date, grayish green crystals up to 35cm, whereas the Befanano crystals are smaller and darker in color. White and blue microcrystals and grains are known from Italy and Kazakhstan. Given the limited number of scandium minerals, and the scarcity of which they occure, scandium is surprisingly abundant in the earth’s crust. Still, all scandium minerals are very rare, and only rarely found in crystals of any size. This is because the scandium ions closely resemples ferric iron, and readily substitutes for this ion in iron bearing, rock forming minerals such as amphiboles and biotite-group minerals.

Thortveitite was first found by Per Schei in the Landsverk 3 quarry, Evje, Norway in 1903, labelled “epidote?” and put in a drawer. Olaus Thortveit was the first person to recognize thortveitite as a potenitally new species based on some crystal fragments found at a quarry in Ljoslandsknipan, Iveland, Norway. Jakob Schetelig in a publication in 1922 mentions that he has measured "part of an about 35 cm crystal with a diameter of 4-5 cm in situ" at this locality. But he also mentions that it was not possible to extract this Thortveitite intact. The holotype material was analysed by Jakob Schetelig in 1910 and published in 1911, given the name Thortveitite to honor Mr. Thortveit for this and other contributions to the mineralogical society. This was not the only honour Olaus Thortveit achieved, in 1914 he donated his impressive mineral collection to the geological museum in Oslo and due to it’s quality he was awarded King Haakon’s Medal of Achievement in Gold.

For a long time, Thortveitite was only known as crystals embedded in quartz and feldspar from the granite pegmatites in the Evje and Iveland area but has now been found at some 30 localities. The mineral occurs in a wide variety of geological environments, including miarolic cavities in granites, aplites and pegmatites, polymetallic ores and skarns, REE bearing quartz veins, metasedimentary rocks, placers and alluvial fans, carbonatites in addition to granitic pegmatites. Seemingly, most of the locations have produced only grains, but some of the miarolitic cavities and some of the granite pegmatites have produced nice crystals.

Thortveitite
Italy
Baveno, Verbano-Cusio-Ossola Province, Piedmont, Italy


White acicular Thortveitite xls 0.9mm	© Chinellato Matteo

The thortveitite is found as small crystals in miarolic cavities in the baveno granite.
We need someone to tell us more about the Thortveitite specimens from this locality.

Thortveitite
Italy
Piedmont, Verbano-Cusio-Ossola Province, Baveno, Oltrefiume, Mount Camoscio, Seula mine (ex Montecatini quarry)


Blue Thortveitite spheres on Orthoclase FOV 2mm	© sergio varvello

Thortveitite occures in miarolic cavities in the granophyre of Cuasso al Monte, Thortveitite occures with other scandium minerals, such as bazzite and others. Thortveitite occurs as tiny greyish or deep blue crystals. The blue varieties contains 2,8 % MnO, and it is believed that traces of Mn3+ causes the blue colour, as this is a strong colouring agent, also responsible for the purple colour of piemontite. This information is extracted from the article “Cesian bazzite and thortveitite from Cuasso Al Monte, Varese Italy: a comparisation with the material from Baveno, and inferred origin” that was printed in the Canadian Mineralogist vol 38, pp 1409-1418 (2000). This article is available on the internet.

These Italian occurances of thortveitite and other scandium minerals are of great importance in understanding why and how scandium minerals are formed in the earths crust, particularily in granite type magmas. Normally scandium is enriched in Fe and Mg rich environments such as gabbros and norite, and not in granite as for these localities.

At least for the Japanese and Swedish locations, there are found evidence of Sc migrating from a surrounding Fe/Mg rich rock into the granite-pegmatites hosting thortveitite. Given the similarity between the Swedish and Norwegian localities, one should not rule out similar mechanisms for the Norwegian locations:

We need someone to tell us more about the Thortveitite specimens from this locality.

Thortvetite
Japan
Honshu Island, Kinki region, Kyoto prefecture, Ohmiya town, Kobe, Shiraishi-yama, Kobe
Thortveitite occurs as good greenish, light green to light greyish green, vitreous, long prismatic crystals to 4cm long and 5mm thick, in parallel growth in light pinkish feldspar in pegmatite at Shiraishi in Kobe-mura (the type locality for kobeite; now part of Ohmiya). (Sakurai et al (1962) Chigaku Kenkyu, 13, 49-51.) Tin-bearing thortveitite at Ohro (Isanago pegmatite mine). (Yamada et al (1980) Chigaku Kenkyu, 31, 205-222; Yokoyama et al (1993) Analyses of natural minerals by energy-dispersive spectrometer. Bulletin of the National Science Museum, ser.C,19:115-126 (in japanese).) Larger specimens can be seen on display at the Masutomi Museum in Kyoto city. Once in a while a specimen is seen on sale at a japanese mineral show, usually only dull and incomplete (broken) crystals, of far lesser quality than the ones on display in museums, so it seems to be quite rare nowadays
(Alfredo Petrov March 18, 2009 )

Thortveitite
Kazakhstan
Djezkazgan Oblast'; Jezkazgan Oblast'), Zhezqazghan Oblysy (Dzezkazgan Oblast'; Balqash (Balkhash; Karatas; Prebalkhashie) Region, Mointy Railway Station, Mointy (Moyynty), Akkuduk (White Well) occurrence


Vial (d~3 mm) with Thortveitite concentrate	© Pavel M. Kartashov

Akkuduk is raremetal ore occurrence, investigated in 1950s and early 60s. It was discovered because of a high radioactivity anomaly discovered by airplane. The ore body has moshroom-like shape and consists of explosive (?) brecciated felsic rocks cemented by hematite and Ferrithorite. So the locality is Y-Th, not polymetallic. The scandium concentration in the ores is rather low. Thortveitite was found in heavy concentrates from the brecciated ores. Because of its unusual blue colour it was initially identified as corundum. Apparently the mineralogist, who had determined this 'corundum" had work before on the Semizbugu corundum deposit, and made this "identification" by sight. Further investigations showed that mineral is pure thortveitite without any Zr or Y impurities. According my own analytical data it contains only small amount of Yb - other HREE and Y are below detection limits. Coloration of the mineral obviously is connected with very low Mn contents ~0.00n % or less.
[Pavel Kartashov 2009]

Thortveitite
Madagascar
Antananarivo Province, Analamanga Region, Ankazobe Pegmatite Field, Anjozorobe Department, Befanamo pegmatite


Thortveitite 1.3cm tall	© Arliguie M

This REE-rich pegmatite is considered the "type locality" of the Y-free variety of thortveitite; befanamite. Approximately 50kg of befanamite was produced as a source of scandium. Most of the production was in the early 50-ties when the price of scandium was high.

Anyone that has any knowledge on this location or other such locations are requested to provide more information.

Thortveitite
Norway
Aust-Agder, Aust-Agder, Kåbuland


Thortveitite xl. on matrix 4cm wide	© Knut Eldjarn

The greatest concentration of Thortveitite mineralization is found in the pegmatite district of Evje/Iveland where thortveitite has been found in some 20-25 different pegmatittic dykes. After it’s initial discovery, more crystals where found and this quickly drew the attention of the global mineralogical community. It did no harm that specimens with crystals approaching 35 cm length were found, and everyone (read national museums) collecting high end specimens wanted specimens of this new mineral which at that time was the only known scandium mineral. The Natural History Museum in London for instance holds 15 specimens from Evje/Iveland, and the Musee de mineralogie, Ecole des mines de Paris has a 20cm crystal found in the “Rumpetrollsynken” or Landsverk2 quarry. It did not take long before this limited market was satisfied and the market for Thortveitite specimens collapsed. This short period after it’s discovery became locally known as the “first klondyke of thortveitite.”

The second “klondyke” came in the 50-ties. A US gouvernment research project on scandium needed ore, and production from the Befanamo pegmatite in Madagascar, and the pegmatites in Evje/Iveland were the only sources of high graded ore. For a few years the price of thortveitite was higher than the price of gold. 1 gram of thortveitie was sold for 13-14 kr/g (equivalent to approx USD30/g today), whereas the gold price was 8,8 kr/g. When a single blast in Tuptane gave 2,5kg of the mineral, no wonder that some of the miners claimed that they had “CEO like salaries” for a few years. The total production until 1960 was estimated to be approximately 50kgs of thortveitite, this according to Bjørlykke who gathered information from the miners. Given that they were paid by the gram, one should assume that a thorough record was kept. Soon the research program was shut down. Evje/Iveland pegmatite district

When I visited the pegmatites in the Iveland Evje area for the first time in 1964 at the age of 15 and spent a week collecting minerals there, I was told many stories by the locals about finds of Thortveitite during the 1950`ies when it was a very valuable ore of Scandium. One of these stories refered to two school boys who had found a piece of Thortveitite of about 1 kg in the tailings of an old pegmatite quarry when walking home from school. With the prices paid at the time (more than gold...) I am sure they were warmly greeted when returning home that evening.¹
1.Knut Eldjarn, email communication 2009.

Today Thortveitite can still be found, and a number of specimens were brought to the mineral collectors market a few years back. These came from the Kåbuland 1 quarry [www.mindat.org]. The price is still quite high for a dull, brittle, grayish green mineral, from 150 USD and upwards into 4 digits for the best specimens. Still the price is too low and the mineral too rare to make “production” profitable in a high cost country like Norway.

The best quarries for Thortveitite was Tuftane and Steane at the Frigstad farm (with approx 2/3 of the total production), whereas the finest crystals came from Mannekleiv and Eptevann . Crystals exceeding 20 cm were found, embedded in quartz or feldspar. Today Kåbuland is considered the best location. Many of the best locations for Thortveitite were relatively small pegmatites and the presence of and xenotime and zircon ( var alvite) are an indication as to the possible presence of Thortveitite especially if these where combined with a quartz core extending towards the surrounding rock.

Thortveitite
Norway
Aust-Agder, Iveland, Frikstad (Frigstad), Tuftane (Tuftan; Tuptane)


A 2 cm crystal of Thortevitite from Tuftan, Iveland, Aust-Agder, Norway	© Knut Eldjarn

Many theories has been published on why such rare mineral appears quite frequently in large crystal in a small area. On a general basis, scandium is not more abundant in neither the general pegmatittic mass nor the surronding amphibolite. It was long believed that the thortveitite bearing pegmatites was deficient in iron, carrying rutile ( ilmenorutile) as the Ti bearing mineral rather than ilmenite. Ilmenite is however the main lead mineral at Kåbuland and a few other occurances, contradicting this theory.

Thortveitite
Sweden
Lappland, Jokkmokk, Ruoutevare


Thortveitite 1cm dark gray green xl in Quartz	© B. Otter

Several granite pegmatites in Sweden contains thortveitite, and one of the pegmatites in the Ruoutevarre mountains is one of them. This locations contains a 1 by 1,5 km pegmatitic body in a gabbro-rock. Within this pegmatitic body a number of coarsly crystallized pegmatite veins has been worked for quartz. A very distinct element exchange between the surronding gabbro and the pegmatites are observed here. The gabbro close to the pegmatites show a significant enrichment of potassium, causing a biotite replacement of pyroxene/amphibole in the gabbro/pegmatite border zones, and plagioclase enrichment in the graphic granite outer zone of the pegmatites. In addition the gabbro is enriched in Si, Ba and Mn. Ti, Mg, Ca, Sr and scandium has been depleted out of the gabbro with as much as 10-20% of the bulk amount present in the border zones.

The pegmatites are enriched in REE minerals and their composition and structure are remarkably similar to the famous Ytterby pegmatite and the Evje/Iveland pegmatite area.

Thortveitite was discovered here in 1978, as the first find in Sweden. Crystals up to 4 cm has been found, associated with plagioclas feldspar and zircon. Thotveitite is a late forming mineral in the primary pegmatite and occationally embeds zircon crystals. The thortveitite from Ruotevarre is very pure and has a dark green colour and are well crystallized. Twins parallell with (110) is common.

.
[Edited by Rock Currier 2009]

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Best T Minerals - Welcome (1 reply)

Rock Currier — Sun, 28 Mar 2010 14:15:14 +0000

In this forum we hope to create articles with pictures about all minerals beginning with the letter T. You are welcomed and encouraged to help create content for this and all the Best Mineral forums. You are encouraged to use the approximate format that has already been developed and exampled in the more extensively developed examples in the Best A Minerals forum. If you would like to take a crack at creating content for a particular mineral, please read over the suggestions and example in the sticky message at the top of the A minerals forum and then add it to this thread entry and I will work with you and walk you through any problems you may encounter. Ill also create a thread entry for the mineral you want to work on and help get you started. You will not be able to create new threads in this forum, unless you are approved as a moderator of the Best Minerals forum. If you have something you think is worth adding to the thread about a particular mineral, just make a thread entry about it, and Ill add it into the thread for that particular entry or at leas ask you for more information about it. There is a huge amount of work to do, so lets get started.

Ideally what we want to know about each significant mineral from each locality is:

1. What is the largest crystal of the mineral that the locality has produced?
2. What do the best specimens from this locality look like and where can one be seen?
3. Does the locality produce a variety of different kinds of specimens of this species, and what do the best of each type look like and how many of them were found etc.
4. What are the associated minerals found with this species and what is its geological setting?
5. How abundant are these specimens and when were they found? A type locality? In other words, how rare are they.
6. How do they compare to other specimens of the same mineral from other localities?
7. How much is it worth. This should probably be optional, but in cases where specimens are worth thousands of dollars we should probably say something of the value of these things.
8. What kind of care and feeding do these specimens require? Are they delicate, radioactive, unstable, color changeable etc.?
9. Are the specimens commonly faked, and if so, how to tell if they are?
10. Are there any interesting stories relating to the collecting of these specimens or their discovery as a new mineral?

Of course this is in reality impractical, but if we keep these questions in mind, we will do a lot better job when writing about them.

Trippkeite (4 replies)

Rock Currier — Thu, 02 Apr 2009 01:57:33 +0000

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Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?

Trippkeite
Cu²⁺As₂³⁺O₄ tetragonal
Chile
Atacama, Copiapo.
Click here to see a picture of Trippkeite.
No specific mine name is locality is known so the mineral was almost certainly from one of the many copper mines in the area. The best specimens show crystals blue green crystals to perhaps 3mm. The mineral has been know since the 1880s and there are very few of these specimens in existence. You will be lucky to ever see one. Bill Pinch had one in his collection that is now in the Royal Ontario Museum of Natural History.
[Rock Currier, 28 December 08]

Click here to view Best Minerals T and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.