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Gadolinite-(Ce) & (Y)
Posted by Olav Revheim
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Gadolinite-(Ce) & (Y) August 13, 2009 05:49PM |
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Registered: 7 years ago Posts: 513 |
Click here to view Best Minerals G 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? I am on very thin ice on a lot of this stuff, and help will be appreciated.
GADOLINITE
Gadolinite-Ce
Ce2FeBe2[O|SiO4]2, Monoclinic
Gadolinite-Y
Y2FeBe2[O|SiO4]2, Monoclinic
The photo I have selected as the main photo is definately not the best quality photo, nor the biggest crystal in the database. The reason I picked it is that the crystal itself is the most perfectly developed gadolinite crystal I have seen, with razor sharp edges and a bright black lustre you normally does not see in crystals this size. I do hope to be able to re-photograph this beauty.
Gadolinite is a rare mineral first described from the famous Ytterby pegmatite outside Stockholm, Sweden. A odd piece of black, coal like rock was found in 1787 by the Swedish army Lieutenant, Karl Axel Arrhenius. He realized that the rock was too heavy for coal, and he believed the unknown rock was an hitterto unknown ore of wolfram, that was recently described. He gave the specimen to the chemist Johan Gadolin of the university of Åbo at Turku, Finland. Gadolin investigated the new mineral and in 1794 he announced that odd black rock contained 38wt percent of a new "earth", which he named Yttria, now Yttrium. He had isolated yttrium oxide. The black rock, was of course an unknown mineral, and it was later named gadolinite. ( John Emsley:2001, Nature's building blocks ISBN-13: 978-0-19-850340-8) (http://en.wikipedia.org/wiki/Johan_Gadolin).Today, Gadolinite is split into two different mineral species based on it’s chemical composition, gadolinite-Y and gadolinite-Ce.
Gadolinite was subject to thorough research by scientists in the 19th century and it is one of the mineral species that had the largest influence on the devolopment of mineralogy and chemistry in this period. After Gadolin's discovery of yttrium, it was found that the oxid of this new element had different properties when extracted from different sources, indicating that it contained impurities from other elements. Carl Gustav Mosander's successful isolation of Erbium and Terbium ( yes, they are both named after Ytterby) in 1843, really sparked the interest of this group of elements ( the Rare Earth Elements or Lanthanides). The British chemist William Crookes (http://en.wikipedia.org/wiki/William_Crookes) summarized the exitement of the time like this:
" The rare earth elements perplex us in our research, baffle us in our speculations and haunt us in our very dreams. They stretch like an unknown sea before us, mocking, mystifying and murmuring strange revelations and possibilities".
In the core of all this exitement was the ugly, black mineral, gadolinite. A total of 5 (Johan Kjellmann 2009) or 7 (Emsley 2001) elements was extracted from gadolinite, namely terbium, erbium,ytterbium, lutetium, holmium, thulium and dysprosium (again Emsley 2001). Properties like metamictization ( the fact that radioactive minerals loose their internal structure over time and become amorphus) and that heat may restore this structure was also first described from gadolinite.
Gadolinite sparked an interest also in the US, where it was found in the great Barringer Hill pegmatite. The mineral rights for this pegmatite was held by Thomas Alva Edison, finding that yttrium oxid was a useful "glower" in electrical lamps. In 1903 he sold the rights of the yttrium lamp the the German chemist Walther Nernst, which was quite successful, both as a scientist and a business man. (http://www.nernst.de/lamp/nernstlamp.htm).
It appears that the mineral can be found in two very distinct geological environments. The largest crystals are found in REE enriched pegmatites embedded in feldspar. These crystals are normally black and metamict amorph, but can nevertheless be found in complex and beautiful crystals. 33 different crystal shapes has been described from Hidra alone, and Goldschmidt has drawn up 30.
Gadolinite can also be found in pockets with a variety of other minerals, either in miarolic cavities in batoliths or alpine type veins. These crystals show a wide variety of habits, colours and appearances, sometimes of very complex chemical composition. Zoned crystals, partly gadolinite-Ce and partly gadolinite-Y can be found. Gadolinite in the alpine occurances can show a rather large variation in chemical composition, grading towards hingganite (Fe deficiant) or darolite ( Ca and B enriched).
Gadolinite is a very interesting mineral for collectors and mineral displays due to it's historical importance, rarity and the number of different crystal shapes.
Most displayed specimens in museums are from Norway, Sweden or Barringer Hill. In particular those museums acquiring high end specimens in the 19th and early 20th century has very fine gadolinite specimens. This includes British Museum, Smithsonian, Ecole du Mines and several German and Scandinavian museums.
Display size specimens with well developed crystals may achieve retail prices exceeding USD 1000, and even incomplete smaller crystals in the 2-3cm / 1 in range are rarely available for less than 100-200 USD
In this text I have included both micromounts and larger crystals in an attempt to show some of the diversity this mineral shows, both in appearance and geological environment. Where several good locations can be found within a small geographical or geological area, I have grouped these ( for instance the Evje/Iveland pegmatite district), and for some of the other countries such as Italy and Austria I have picked one or a few location as an example of how the mineral occurs in that specific country. In doing this I may unintentionally leave out several good locations, and any suggestion/correction will be highly appreciated.
Gadolinite-Y
Austria
Tyrol, North Tyrol, Ziller valley,Zamser Grund (Zams valley), Schrammacher Mt, Oberschrammach glacier
The Schrammer mountain is located in the western part of the Tauern window in the Alps. The Tauern window consists of high grade metamorphic rocks ( greenschist to amphibolite facies). Apparantly, the Scrammer mountains consist of metamorphosed granodiorites and granites. Hydrothermal veins postdating the orogony are enriched on REE elements, thus forming small crystals of several rare minerals in vugs. Gadolinite is one of them, and it can be found in bottle-green crystals several mm tall.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Italy
Lombard, Varese Province, Ceresio Valley, Cuasso al Monte
Chemical and paragenetic studies were performed on gadolinite-group minerals occurring in miarolitic pink granite and granophyric leucogranite of the subvolcanic Hercynian plutons at Baveno and Cuasso al Monte, Southern Alps, Italy. In the localities investigated, gadolinite-group minerals are hosted in massive pegmatite, in aplite, and in miarolitic cavities having different degrees of evolution. The petrological relations indicate that progressive crystallization has occurred from magmatic through to hydrothermal conditions. At Baveno, Ce-rich gadolinite-(Y) (with Sigma REE > Y) formed during the primitive stages of pegmatite crystallization. Gadolinite-(Y) (with Sigma REE < Y) formed in pegmatites and granophyric aplites during primitive to moderately evolved stages of these dikes, grading towards hingganite-Y in hydrothermal cavities.
More information on this and/or similar locations will be highly appreciated.
Italy
Trentino-Alto Adige, Bolzano Province (South Tyrol), Vizze Valley (Pfitsch Valley), San Giacomo, Vizze pass (Pfitsch pass)
Vizze Pass is another area where rare minerals can be found in alpine veins in metamorphic rocks in the Alps.
"Here I have found the gadolinite in small but well formed crystals of quality it gemmates.
Unfortunately also in this place as in that preceding they are very rare, but at times looking for with some fortune they are found.
The rock is always metamorphic and more precisely an quartzporphyr in a conglomerate gneiss absorbed.
Very interesting the fact that is the same fissure mineralized where the genthelvite and others rare mineral is found." (Manuelle Moro 2009)
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Norway
Vest-Agder, Hidra, (Hitterøe)
The Hidra granite pegmatites is one of the great locations for gadolinites and they were worked for quartz and feldspar in the 19th century. At least 10 different pegmatites( max 6 m wide and 100m long) contained gadolinite, and in particular Urstad and Igletjern ( Eldjarn 2009) supplied large crystals. Hidra became the main source of large gadolinites after and in addition to the Ytterby pegmatite at the time. The university of Stockholm has 35 gadolinite samples from Hidra ( Brotzen 1959). Well developed crystals approaching 40 cm could be found. Gadolinite from Hidra is represented in several museums across Europe and the best can " be admired in the display of the Geological museum in Bergen. I hope you will get some pictures of those." ( Knut Eldjarn 2009).
The paper "The granite pegmatites of Hitterø" (Olge Adamson 1942) provides and excellent summary of the Hidra pegmatites and their minerals:
" Gadolinite is found in all the much worked quarries, but in varying amounts. It occurs partly as beautiful crystals of about 1 cm magnitude or smaller, partly as about 5 cm large crystals, then mostly with biotite, partly as enormous crystals up to 40 cm length. It is always found altered into a metamict state. The faces sometimes have a yellow-white covering of tengerite. Gadolinite has been observed in quartz, microcline, oligioclase, biotite and muscovite. It is clear that the formation of gadolinite exteded over a long period. the small beautifully crystallized, form rich gadolinites are obviously formed first- The crystals that grow upon biotite and consequently are younger than biotite, are poor in forms and are generally irregularly developed. The big gadolinites sometimes show a contemporary crystallization with mica and feldspar. "
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Norway
Aust Agder, Setesdalen, Evje
Aust Agder, Setesdalen, Iveland
In the Evje/Iveland area, several hundred small quarries has been worked for feldspar, quartz, mica and REE minerals. All pegmaties containing REE minerals lies in an amphibolite body. Old specimens, such as the one from British museum ( see link above) are often labeled Sætersdalen, Setesdalen or similar. Good crystals of gadolinite has been found in several quarries in the area, and dark REE rich garnets and allanite are good lead minerals. The best area has been the Frikstad area in northern Iveland, where the quarries Slobrekka, Tuftane and Birkeland stands out. Gadolinite was one of the profitable by-products from the feldspar production, and fairly decent records of the production has been kept. The largest known crystal was 500 kg’s, and stood out in the pegmatite as “ a small squatting man”, and crystals exceeding 100 kgs are known from several of the quarries. Gadolinite from here show a remarkable complex crystal development, and numerous crystal shapes. Most of the larger (> 1 in.) specimens I have seen for sale has been from this area, often older specimens, although good finds has been made the last 5-10 years as well. ( ref [www.mindat.org] )
Aust-Agder, Iveland, Frikstad (Frigstad)
This is a general geographical area in the northern part of the Iveland Municipality. Older specimens labeled Frikstad or even Iveland or Setesdal would normally have it’s origin in one of the quarries in this area. It is virtually impossible to tell which one. I have picked three of the quarries for further description:
Aust-Agder, Iveland, , Frikstad (Frigstad),Slobrekka (Frikstad 7) pegmatite
The largest gadolinite crystal has been found here ( +/- 500kg), and it has been one of the richest sources of gadolinites in the area. Slobrekka is the source of the best modern finds ( the last 10 years) with black, shiny and complex crystals appraoching 10 cm.
Aust-Agder, Iveland, , Frikstad (Frigstad), Tuftan pegmatite,
Small quarry, now filled with garbage, was in the 1950-ties and 60ties an abundant source of gadolinite, davidite, thortveitite and other minerals.
Aust-Agder, Iveland, Birkeland, Iveland, Aust Agder
These quarries occationally produces some specimens even today. The 4 quarries on the Birkeland farm has produced several hundred kilograms of gadolinite. This is the most likely source of staircase cystal groups..
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Norway
Nordland, Tysfjord, Hundholmen
The Hundholmen pegmatite is one of the largest and most mineral rich of a number of granite pegmatites in the Tysfjord area of Northern Norway. It is the type locality of hundholmenite. The pegmatites are rich in REE-minerals. Gadolinite-Y has been found in some of the pegmatites mainly in the border zone of large masses of yttrian Fluorite and as grains embedded in the yttrian fluorite.Good crystals to several mm have also been found and more rarely at the Hundholmen pegmatite larger and well formed crystals to about 1,5 cm are known. The Gadolinite-Y from Hundholmen is bottle-green and non-metamict which is unusual for Gadolinites from REE-pegmatites ( Eldjarn 2009)
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Sweden
Dalarne, Falun, Kårarvet (Kararfvet; Korarfvet)
There are two gadolinite bearing pegmatites on the Kårarvet farm, termed the "old" and the "new" location, where the new occurance was described for the first time in 1860. The current state of these locations are unknown. Gadolinite was found in elongated wedgeshaped pieces without obvious crystal shape, often enclosed in a thick rusty crust of alteration products, sometimes completely altered. Gadolinite could however, as a rarity, be found in well developed crystals like the one pictured. Gadolinite occured in a coarse grained quartz/microcline/plagioclase/muscovite pegmatites with garnet and other Y/REE minerals.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Sweden
Uppland, Vaxholm, Resarö, Ytterby
This location was the earliest pegmatite opened for production of quartz and feldspar in Sweden. It was in operation from about 1794 to 1933.Even today, more than 75 years after end of operation, this mine is an icon for everyone interested in REE minerals and and elements.
Ytterby is the type locality for gadolinite, yttrotantalite and tengerite, all found before Levinson (A suffix like gadolinite-(Y), or gadolinite (Ce) type is known as a Levinson modifier, named after Alfred Levinson who introduced this procedure in a paper in 1966, ).
The pegmatite is almost vertical with a ”pinch and swell” structure. The 5-6 expanding “swell” areas could be followed down to approx. 160m below surface. The pegmatites were worked for both quartz and feldspar. The rare minerals, REE-Ta-Nb-Ti oxides, REE phophates, - carbonates and – silicates was more abundant in the upper parts of the pegmatite, to around 50-60m below surface, with the uppermost 25 m as the richest.
The Ta/Nb fraction was higher in the upper portion of the pegmatite than further down. The Ta dominant oxides yttrotantalite and formanite was more common near the surface, whereas fergusonite became more common towards the deeper parts of the mine in the middle of the 19th century.
The gadolinite occurs in feldspar with biotite or muscovite, often associated with the Ta-oxides. The crystals varies in size from an approximate pea size up a large fist. It was difficult to free undamaged crystals ( as they where embedded in feldspar), but when successful specimens of very high quality was the result. The gadolinite paragenesis is frequently brecciated and pseudomorphosed to amongst other xenotime-rich nodules. (Johan Kjellmann 2009). Gadolinite was found with biotite that has often restricted the development of the gadolinite crystals. It was also found embedded in microcline, most frequently with poorly developed crystals, but quite often as perfectly developed crystals. A total of 14 different crystal shapes are described. Gadolinite was quite frequent at the location, or "gadoliniten.....påtraffats i mycket riklig mangd" to use the words of W.Peterson, 1890 in Studier övfer gadolinit ( studies on gadolinite)
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Switzerland
Wallis (Valais), Goms, Oberwald, Furka basis tunnel (west section)
During tunnel construction work, a number of different minerals was found
The identification on these light gadolinites from the alpine occurances has been questioned ( Stefan Wolfried, Pavel Kartashov and Uwe Kolitsch 2009). Johan Kjellmann (2009) has confirmed this uncertainty by providing the following information: "Demartin et al. 1993 (Can. Min. vol. 31, pp. 127-136) has the material you're talking about. Abstract pretty much verify your (Uwe and Pavel) statements:
Gadolinite-(Y) specimens from various localities in the Alps have been examined by electron microprobe and single crystal X-ray diffraction. In general, dysprosium is the most abundant rare earth, although a few samples contain approximately equal amounts of Dy and Yb, and in one instance, Gd predominates. In contrast to many non-Alpine occurrences, most of these specimens show only limited amounts of the lighter REE. There is an almost constant presence of calcium (up to 4 wt% CaO, and possibly twice that amount for more questionable samples); iron is often markedly deficient with respect to the theoretical formula, and in at least one case (Glogstafelberg), the material should more properly be called hingganite-(Y) (4.0 wt% FeO). In some specimens, a significant substitution of B for Be (up to about 4.2 wt% B2O3) can be deduced from crystal-structure data, on the basis of linear interpolation of the measured Be-O bond lengths with respect to other gadolinite-group minerals. This substitution is more extensive for specimens high in Ca and low in Fe, and which therefore grade toward darolite. No evidence for replacement of Si by B has been found. Minor amounts of thorium (up to 0.4 wt% ThO2) commonly are present, and uranium (0.3 wt% UO2) was found in one specimen. As for xeootime and monazite, the behavior of Y is not uniquely determined by the ionic radius, some specimens being especially enriched in this element with respect to the middle-heavy rare earths (up to 41.5 wt% Y2O3). "
More information on this and/or similar locations will be highly appreciated.
Gadolinite-?
USA
Colorado, Jefferson Co, Clear Creek pegmatite Province,Roscoe Beryl Mine (Roscoe pegmatite)
On the locality pages of Mindat, the gadolinite from here is listed as gadolinite-Ce, I have chosen to question this as the pegmatite is a granite pegmatite apparantly with Y/Ce >1. Well developed monoclinic crystals has been found here, the largest partial crystal 11 cm. There are several gadolinite bearing pegmatites in this area, and gadolinite is found embedded in microcine, and is interpreted to be formed at the same time as the feldspar. At the Roscoe pegmatite, gadolinite has been found embedded in albite. It is believed that the albite has replaced microcline without significantly altering the gadiolinite.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
USA
Texas, Llano Co, Bluffton, Baringer Hill (Barringer Hill), Bluffton,
The Baringer Hill pegmatite is an almost mythical REE pegmatite. It is intruded into a granite, which in turn is intruded into the Valley Spring and Packsaddle metamorphic formations. There are several other pegmatites in the area, and one of them contains REE minerals. (see [www.mindat.org]) The pegmatite was discovered in 1887 and worked for feldspar, gadolinite and other minerals on and off until 1907. Today the the pegmatite lies under water, as the Lake Buchanan was formed as a reservoir for drinking water and hydroelectricity. The construction of the over 2 mile wide Buchanan dam was completed in 1939.
The pegmatite itself was descriped as a 40ft hill, 100ft wide and 250 ft long. It had a zone of graphic granite along the border, then a internediate zone consisting of mainly microcline and a quartz core that reach 40ft width at the widest. The REE minerals was quantitively rare, but could still, occationatily form large crystals. Gadolinite-Y is one of the minerals that was found in very good, very large crystals. Crystals or crystalline masses exceeding 200 lbs has been reported, and the 73 lbs crystal group pictured in the wikipedia article on Baringer Hill is second to none. (http://en.wikipedia.org/wiki/Barringer_Hill). Crystals from here are represented in most of the major museums collecting minerals in the second half of the 19th century, buth in the US and in Europe. At Baringer Hill as for Ytterby, Hidra and Evje/Iveland gadolinite can be found both fresh and as partly altered crystals.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Gadolinite-Ce
Austria
Gastein Valley, Böckstein, Moos Outcrop
Gastein Valley, Böckstein,Municipal Quarry
The Municipal Quarry location is a long time abandoned quarry in a in a granittic gneis with crossing aplite and pegmatite veins. The mineralization occurs in clefts in the rock, and small (micros), but well developed gadolinite-Ce crystals has been found. The Municipial quarry has only one cleft with Gadolinite in the left corner of the quarry. Some people have found Gadolinite in the last years, I have found my only Gadolinite in 2007. Interesting at the Municipial quarry is that the Gadolinite xls are mostly well terminated and not metamict. Most Gadolionite xls are associated with Muskovite, Chlorite, well terminated Aeschynite-(Y) and Titanite, sometimes with Rutile or Brookite. (Information received from Martin Slama-2009)
A similar but better gadolinite locality is the "Moos" which is located about 150m behind the Municipial quarry. At this location Gadolinite-(Y) is quite common and can also be found today. From this location the largest Austrian Gadolinite is known, it is a perfect xtl with about 1,5cm and has been found by Roland Winkler! However the location is really small even today Gadolinite can be found. The last found I know is only one week ago. (Information received from Martin Slama-2009).
I have treated these two localities as one location in this article due to their geological and geographical proximity. According to the Mindat locality pages, the mineralization at the Moos location is in the same rock formation as the Municipality Quarry. I find it quite interesting though that both gadolinite species are found within such a small area.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Ce
USA
Washington, Okanogan Co, Golden Horn Batholith, Washington Pass
The Golden Horn batholith is a quite recent (~45 mill years) alkaline granite enriched in REE. The gadolinite is found as small (mm sized) brownish crystals in miarolic cavities in the rock. Several great location photos from the area are uploaded to mindat.
In another thread on refering to a gadolinite crystal from this location, Saul Kroti ( 2009) states the following:
"This gadolinite, was found to be metamict, and required gradual recrystallization by annealing for forty-eight hours at 700˚ C, before a distinct diffraction pattern could be obtained. Accomplished by John Attard, December 2008, the pattern matched gadolinite-(Ce) Type material from the Bjørkehalen pegmatite, near Buer, Norway, reported by Segalstad and Larsen (1978).
In many samples the outer-most zones or encrustations are yttrium dominant, (in 8 fold coordination), but in the inner cores Ce dominates Y by a large margin. I do not yet know how consistent this observation will prove to be. But that was so for thirty crystals examined.
Oscillatory zones with light and dark bands examined in polished thick section show only the most subtle variations of composition, not yet summarized. But in this specimen the texture is not what you find in the crystals with the dark and light bands which you see only by surprise in BSE/SEM, but not in photomicrography."
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Ce
Norway
Telemark, Porsgrunn, Bjørkedalen, Buer
This is the type locality for gadolinite-Ce. The gadolinite-Ce crystals are found embedded in a syenite pegmatite of the same type as the famous Langesundfjord pegmatites. Gadolinite-Ce has also been found in a few other pegmatites in the area. The crystals are black and metamict amorph. More information on this and/or similar locations will be highly appreciated.
More information on this and/or similar locations will be highly appreciated.
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Edited 24 time(s). Last edit at 03/25/2012 01:56AM by Rock Currier.
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? I am on very thin ice on a lot of this stuff, and help will be appreciated.
GADOLINITE
Gadolinite-Ce
Ce2FeBe2[O|SiO4]2, Monoclinic
Gadolinite-Y
Y2FeBe2[O|SiO4]2, Monoclinic
The photo I have selected as the main photo is definately not the best quality photo, nor the biggest crystal in the database. The reason I picked it is that the crystal itself is the most perfectly developed gadolinite crystal I have seen, with razor sharp edges and a bright black lustre you normally does not see in crystals this size. I do hope to be able to re-photograph this beauty.
Gadolinite is a rare mineral first described from the famous Ytterby pegmatite outside Stockholm, Sweden. A odd piece of black, coal like rock was found in 1787 by the Swedish army Lieutenant, Karl Axel Arrhenius. He realized that the rock was too heavy for coal, and he believed the unknown rock was an hitterto unknown ore of wolfram, that was recently described. He gave the specimen to the chemist Johan Gadolin of the university of Åbo at Turku, Finland. Gadolin investigated the new mineral and in 1794 he announced that odd black rock contained 38wt percent of a new "earth", which he named Yttria, now Yttrium. He had isolated yttrium oxide. The black rock, was of course an unknown mineral, and it was later named gadolinite. ( John Emsley:2001, Nature's building blocks ISBN-13: 978-0-19-850340-8) (http://en.wikipedia.org/wiki/Johan_Gadolin).Today, Gadolinite is split into two different mineral species based on it’s chemical composition, gadolinite-Y and gadolinite-Ce.
Gadolinite was subject to thorough research by scientists in the 19th century and it is one of the mineral species that had the largest influence on the devolopment of mineralogy and chemistry in this period. After Gadolin's discovery of yttrium, it was found that the oxid of this new element had different properties when extracted from different sources, indicating that it contained impurities from other elements. Carl Gustav Mosander's successful isolation of Erbium and Terbium ( yes, they are both named after Ytterby) in 1843, really sparked the interest of this group of elements ( the Rare Earth Elements or Lanthanides). The British chemist William Crookes (http://en.wikipedia.org/wiki/William_Crookes) summarized the exitement of the time like this:
" The rare earth elements perplex us in our research, baffle us in our speculations and haunt us in our very dreams. They stretch like an unknown sea before us, mocking, mystifying and murmuring strange revelations and possibilities".
In the core of all this exitement was the ugly, black mineral, gadolinite. A total of 5 (Johan Kjellmann 2009) or 7 (Emsley 2001) elements was extracted from gadolinite, namely terbium, erbium,ytterbium, lutetium, holmium, thulium and dysprosium (again Emsley 2001). Properties like metamictization ( the fact that radioactive minerals loose their internal structure over time and become amorphus) and that heat may restore this structure was also first described from gadolinite.
Gadolinite sparked an interest also in the US, where it was found in the great Barringer Hill pegmatite. The mineral rights for this pegmatite was held by Thomas Alva Edison, finding that yttrium oxid was a useful "glower" in electrical lamps. In 1903 he sold the rights of the yttrium lamp the the German chemist Walther Nernst, which was quite successful, both as a scientist and a business man. (http://www.nernst.de/lamp/nernstlamp.htm).
It appears that the mineral can be found in two very distinct geological environments. The largest crystals are found in REE enriched pegmatites embedded in feldspar. These crystals are normally black and metamict amorph, but can nevertheless be found in complex and beautiful crystals. 33 different crystal shapes has been described from Hidra alone, and Goldschmidt has drawn up 30.
Gadolinite can also be found in pockets with a variety of other minerals, either in miarolic cavities in batoliths or alpine type veins. These crystals show a wide variety of habits, colours and appearances, sometimes of very complex chemical composition. Zoned crystals, partly gadolinite-Ce and partly gadolinite-Y can be found. Gadolinite in the alpine occurances can show a rather large variation in chemical composition, grading towards hingganite (Fe deficiant) or darolite ( Ca and B enriched).
Gadolinite is a very interesting mineral for collectors and mineral displays due to it's historical importance, rarity and the number of different crystal shapes.
Most displayed specimens in museums are from Norway, Sweden or Barringer Hill. In particular those museums acquiring high end specimens in the 19th and early 20th century has very fine gadolinite specimens. This includes British Museum, Smithsonian, Ecole du Mines and several German and Scandinavian museums.
Display size specimens with well developed crystals may achieve retail prices exceeding USD 1000, and even incomplete smaller crystals in the 2-3cm / 1 in range are rarely available for less than 100-200 USD
In this text I have included both micromounts and larger crystals in an attempt to show some of the diversity this mineral shows, both in appearance and geological environment. Where several good locations can be found within a small geographical or geological area, I have grouped these ( for instance the Evje/Iveland pegmatite district), and for some of the other countries such as Italy and Austria I have picked one or a few location as an example of how the mineral occurs in that specific country. In doing this I may unintentionally leave out several good locations, and any suggestion/correction will be highly appreciated.
Gadolinite-Y
Austria
Tyrol, North Tyrol, Ziller valley,Zamser Grund (Zams valley), Schrammacher Mt, Oberschrammach glacier
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| Gadolinite-(Y) 3mm perfect crystal | © Manuele Moro |
The Schrammer mountain is located in the western part of the Tauern window in the Alps. The Tauern window consists of high grade metamorphic rocks ( greenschist to amphibolite facies). Apparantly, the Scrammer mountains consist of metamorphosed granodiorites and granites. Hydrothermal veins postdating the orogony are enriched on REE elements, thus forming small crystals of several rare minerals in vugs. Gadolinite is one of them, and it can be found in bottle-green crystals several mm tall.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Italy
Lombard, Varese Province, Ceresio Valley, Cuasso al Monte
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| Gadolinite-(Y) FOV 2,4mm | © Elmar Lackner |
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| ~3mm Gadolinite-(Y) on Orthoclase | © |
Chemical and paragenetic studies were performed on gadolinite-group minerals occurring in miarolitic pink granite and granophyric leucogranite of the subvolcanic Hercynian plutons at Baveno and Cuasso al Monte, Southern Alps, Italy. In the localities investigated, gadolinite-group minerals are hosted in massive pegmatite, in aplite, and in miarolitic cavities having different degrees of evolution. The petrological relations indicate that progressive crystallization has occurred from magmatic through to hydrothermal conditions. At Baveno, Ce-rich gadolinite-(Y) (with Sigma REE > Y) formed during the primitive stages of pegmatite crystallization. Gadolinite-(Y) (with Sigma REE < Y) formed in pegmatites and granophyric aplites during primitive to moderately evolved stages of these dikes, grading towards hingganite-Y in hydrothermal cavities.
More information on this and/or similar locations will be highly appreciated.
Italy
Trentino-Alto Adige, Bolzano Province (South Tyrol), Vizze Valley (Pfitsch Valley), San Giacomo, Vizze pass (Pfitsch pass)
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| meaningful gadolinite-(Y) crystal 2,8 mms on quartz | © Manuele Moro |
Vizze Pass is another area where rare minerals can be found in alpine veins in metamorphic rocks in the Alps.
"Here I have found the gadolinite in small but well formed crystals of quality it gemmates.
Unfortunately also in this place as in that preceding they are very rare, but at times looking for with some fortune they are found.
The rock is always metamorphic and more precisely an quartzporphyr in a conglomerate gneiss absorbed.
Very interesting the fact that is the same fissure mineralized where the genthelvite and others rare mineral is found." (Manuelle Moro 2009)
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Norway
Vest-Agder, Hidra, (Hitterøe)
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| Gadolinite-Y 5.3 x 4.8 x 1.9 cm | © Rob Lavinsky |
The Hidra granite pegmatites is one of the great locations for gadolinites and they were worked for quartz and feldspar in the 19th century. At least 10 different pegmatites( max 6 m wide and 100m long) contained gadolinite, and in particular Urstad and Igletjern ( Eldjarn 2009) supplied large crystals. Hidra became the main source of large gadolinites after and in addition to the Ytterby pegmatite at the time. The university of Stockholm has 35 gadolinite samples from Hidra ( Brotzen 1959). Well developed crystals approaching 40 cm could be found. Gadolinite from Hidra is represented in several museums across Europe and the best can " be admired in the display of the Geological museum in Bergen. I hope you will get some pictures of those." ( Knut Eldjarn 2009).
The paper "The granite pegmatites of Hitterø" (Olge Adamson 1942) provides and excellent summary of the Hidra pegmatites and their minerals:
" Gadolinite is found in all the much worked quarries, but in varying amounts. It occurs partly as beautiful crystals of about 1 cm magnitude or smaller, partly as about 5 cm large crystals, then mostly with biotite, partly as enormous crystals up to 40 cm length. It is always found altered into a metamict state. The faces sometimes have a yellow-white covering of tengerite. Gadolinite has been observed in quartz, microcline, oligioclase, biotite and muscovite. It is clear that the formation of gadolinite exteded over a long period. the small beautifully crystallized, form rich gadolinites are obviously formed first- The crystals that grow upon biotite and consequently are younger than biotite, are poor in forms and are generally irregularly developed. The big gadolinites sometimes show a contemporary crystallization with mica and feldspar. "
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Norway
Aust Agder, Setesdalen, Evje
Aust Agder, Setesdalen, Iveland
In the Evje/Iveland area, several hundred small quarries has been worked for feldspar, quartz, mica and REE minerals. All pegmaties containing REE minerals lies in an amphibolite body. Old specimens, such as the one from British museum ( see link above) are often labeled Sætersdalen, Setesdalen or similar. Good crystals of gadolinite has been found in several quarries in the area, and dark REE rich garnets and allanite are good lead minerals. The best area has been the Frikstad area in northern Iveland, where the quarries Slobrekka, Tuftane and Birkeland stands out. Gadolinite was one of the profitable by-products from the feldspar production, and fairly decent records of the production has been kept. The largest known crystal was 500 kg’s, and stood out in the pegmatite as “ a small squatting man”, and crystals exceeding 100 kgs are known from several of the quarries. Gadolinite from here show a remarkable complex crystal development, and numerous crystal shapes. Most of the larger (> 1 in.) specimens I have seen for sale has been from this area, often older specimens, although good finds has been made the last 5-10 years as well. ( ref [www.mindat.org] )
Aust-Agder, Iveland, Frikstad (Frigstad)
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| Amazing group of gadolinite-Y crystals to 5 cm | © Knut Eldjarn |
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| 9,5 cm crystal | © A. Michalsen |
This is a general geographical area in the northern part of the Iveland Municipality. Older specimens labeled Frikstad or even Iveland or Setesdal would normally have it’s origin in one of the quarries in this area. It is virtually impossible to tell which one. I have picked three of the quarries for further description:
Aust-Agder, Iveland, , Frikstad (Frigstad),Slobrekka (Frikstad 7) pegmatite
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| gadolinite-Y 6,5 cm crystal | © Olav Revheim |
The largest gadolinite crystal has been found here ( +/- 500kg), and it has been one of the richest sources of gadolinites in the area. Slobrekka is the source of the best modern finds ( the last 10 years) with black, shiny and complex crystals appraoching 10 cm.
Aust-Agder, Iveland, , Frikstad (Frigstad), Tuftan pegmatite,
Small quarry, now filled with garbage, was in the 1950-ties and 60ties an abundant source of gadolinite, davidite, thortveitite and other minerals.
Aust-Agder, Iveland, Birkeland, Iveland, Aust Agder
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| gadolinite-Y 8,5 cm crystal | © OT. Ljostad |
These quarries occationally produces some specimens even today. The 4 quarries on the Birkeland farm has produced several hundred kilograms of gadolinite. This is the most likely source of staircase cystal groups..
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Norway
Nordland, Tysfjord, Hundholmen
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| gadolinite-Y 1,5 cm crystal | © Knut Eldjarn |
The Hundholmen pegmatite is one of the largest and most mineral rich of a number of granite pegmatites in the Tysfjord area of Northern Norway. It is the type locality of hundholmenite. The pegmatites are rich in REE-minerals. Gadolinite-Y has been found in some of the pegmatites mainly in the border zone of large masses of yttrian Fluorite and as grains embedded in the yttrian fluorite.Good crystals to several mm have also been found and more rarely at the Hundholmen pegmatite larger and well formed crystals to about 1,5 cm are known. The Gadolinite-Y from Hundholmen is bottle-green and non-metamict which is unusual for Gadolinites from REE-pegmatites ( Eldjarn 2009)
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Sweden
Dalarne, Falun, Kårarvet (Kararfvet; Korarfvet)
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| gadolinite-Y field of view 35mm | © C.H.M.-Schäfer |
There are two gadolinite bearing pegmatites on the Kårarvet farm, termed the "old" and the "new" location, where the new occurance was described for the first time in 1860. The current state of these locations are unknown. Gadolinite was found in elongated wedgeshaped pieces without obvious crystal shape, often enclosed in a thick rusty crust of alteration products, sometimes completely altered. Gadolinite could however, as a rarity, be found in well developed crystals like the one pictured. Gadolinite occured in a coarse grained quartz/microcline/plagioclase/muscovite pegmatites with garnet and other Y/REE minerals.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Sweden
Uppland, Vaxholm, Resarö, Ytterby
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| gadolinite-Y crystals 2cm | © AÖ 2007 |
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| gadolinite-Y field of view 10cm | © C.H.M.-Schäfer |
This location was the earliest pegmatite opened for production of quartz and feldspar in Sweden. It was in operation from about 1794 to 1933.Even today, more than 75 years after end of operation, this mine is an icon for everyone interested in REE minerals and and elements.
Ytterby is the type locality for gadolinite, yttrotantalite and tengerite, all found before Levinson (A suffix like gadolinite-(Y), or gadolinite (Ce) type is known as a Levinson modifier, named after Alfred Levinson who introduced this procedure in a paper in 1966, ).
The pegmatite is almost vertical with a ”pinch and swell” structure. The 5-6 expanding “swell” areas could be followed down to approx. 160m below surface. The pegmatites were worked for both quartz and feldspar. The rare minerals, REE-Ta-Nb-Ti oxides, REE phophates, - carbonates and – silicates was more abundant in the upper parts of the pegmatite, to around 50-60m below surface, with the uppermost 25 m as the richest.
The Ta/Nb fraction was higher in the upper portion of the pegmatite than further down. The Ta dominant oxides yttrotantalite and formanite was more common near the surface, whereas fergusonite became more common towards the deeper parts of the mine in the middle of the 19th century.
The gadolinite occurs in feldspar with biotite or muscovite, often associated with the Ta-oxides. The crystals varies in size from an approximate pea size up a large fist. It was difficult to free undamaged crystals ( as they where embedded in feldspar), but when successful specimens of very high quality was the result. The gadolinite paragenesis is frequently brecciated and pseudomorphosed to amongst other xenotime-rich nodules. (Johan Kjellmann 2009). Gadolinite was found with biotite that has often restricted the development of the gadolinite crystals. It was also found embedded in microcline, most frequently with poorly developed crystals, but quite often as perfectly developed crystals. A total of 14 different crystal shapes are described. Gadolinite was quite frequent at the location, or "gadoliniten.....påtraffats i mycket riklig mangd" to use the words of W.Peterson, 1890 in Studier övfer gadolinit ( studies on gadolinite)
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Switzerland
Wallis (Valais), Goms, Oberwald, Furka basis tunnel (west section)
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| gadolinite-Y field of view 3mm | © Stephan Wolfsried |
The identification on these light gadolinites from the alpine occurances has been questioned ( Stefan Wolfried, Pavel Kartashov and Uwe Kolitsch 2009). Johan Kjellmann (2009) has confirmed this uncertainty by providing the following information: "Demartin et al. 1993 (Can. Min. vol. 31, pp. 127-136) has the material you're talking about. Abstract pretty much verify your (Uwe and Pavel) statements:
Gadolinite-(Y) specimens from various localities in the Alps have been examined by electron microprobe and single crystal X-ray diffraction. In general, dysprosium is the most abundant rare earth, although a few samples contain approximately equal amounts of Dy and Yb, and in one instance, Gd predominates. In contrast to many non-Alpine occurrences, most of these specimens show only limited amounts of the lighter REE. There is an almost constant presence of calcium (up to 4 wt% CaO, and possibly twice that amount for more questionable samples); iron is often markedly deficient with respect to the theoretical formula, and in at least one case (Glogstafelberg), the material should more properly be called hingganite-(Y) (4.0 wt% FeO). In some specimens, a significant substitution of B for Be (up to about 4.2 wt% B2O3) can be deduced from crystal-structure data, on the basis of linear interpolation of the measured Be-O bond lengths with respect to other gadolinite-group minerals. This substitution is more extensive for specimens high in Ca and low in Fe, and which therefore grade toward darolite. No evidence for replacement of Si by B has been found. Minor amounts of thorium (up to 0.4 wt% ThO2) commonly are present, and uranium (0.3 wt% UO2) was found in one specimen. As for xeootime and monazite, the behavior of Y is not uniquely determined by the ionic radius, some specimens being especially enriched in this element with respect to the middle-heavy rare earths (up to 41.5 wt% Y2O3). "
More information on this and/or similar locations will be highly appreciated.
Gadolinite-?
USA
Colorado, Jefferson Co, Clear Creek pegmatite Province,Roscoe Beryl Mine (Roscoe pegmatite)
On the locality pages of Mindat, the gadolinite from here is listed as gadolinite-Ce, I have chosen to question this as the pegmatite is a granite pegmatite apparantly with Y/Ce >1. Well developed monoclinic crystals has been found here, the largest partial crystal 11 cm. There are several gadolinite bearing pegmatites in this area, and gadolinite is found embedded in microcine, and is interpreted to be formed at the same time as the feldspar. At the Roscoe pegmatite, gadolinite has been found embedded in albite. It is believed that the albite has replaced microcline without significantly altering the gadiolinite.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
USA
Texas, Llano Co, Bluffton, Baringer Hill (Barringer Hill), Bluffton,
The Baringer Hill pegmatite is an almost mythical REE pegmatite. It is intruded into a granite, which in turn is intruded into the Valley Spring and Packsaddle metamorphic formations. There are several other pegmatites in the area, and one of them contains REE minerals. (see [www.mindat.org]) The pegmatite was discovered in 1887 and worked for feldspar, gadolinite and other minerals on and off until 1907. Today the the pegmatite lies under water, as the Lake Buchanan was formed as a reservoir for drinking water and hydroelectricity. The construction of the over 2 mile wide Buchanan dam was completed in 1939.
The pegmatite itself was descriped as a 40ft hill, 100ft wide and 250 ft long. It had a zone of graphic granite along the border, then a internediate zone consisting of mainly microcline and a quartz core that reach 40ft width at the widest. The REE minerals was quantitively rare, but could still, occationatily form large crystals. Gadolinite-Y is one of the minerals that was found in very good, very large crystals. Crystals or crystalline masses exceeding 200 lbs has been reported, and the 73 lbs crystal group pictured in the wikipedia article on Baringer Hill is second to none. (http://en.wikipedia.org/wiki/Barringer_Hill). Crystals from here are represented in most of the major museums collecting minerals in the second half of the 19th century, buth in the US and in Europe. At Baringer Hill as for Ytterby, Hidra and Evje/Iveland gadolinite can be found both fresh and as partly altered crystals.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Y
Gadolinite-Ce
Austria
Gastein Valley, Böckstein, Moos Outcrop
Gastein Valley, Böckstein,Municipal Quarry
The Municipal Quarry location is a long time abandoned quarry in a in a granittic gneis with crossing aplite and pegmatite veins. The mineralization occurs in clefts in the rock, and small (micros), but well developed gadolinite-Ce crystals has been found. The Municipial quarry has only one cleft with Gadolinite in the left corner of the quarry. Some people have found Gadolinite in the last years, I have found my only Gadolinite in 2007. Interesting at the Municipial quarry is that the Gadolinite xls are mostly well terminated and not metamict. Most Gadolionite xls are associated with Muskovite, Chlorite, well terminated Aeschynite-(Y) and Titanite, sometimes with Rutile or Brookite. (Information received from Martin Slama-2009)
A similar but better gadolinite locality is the "Moos" which is located about 150m behind the Municipial quarry. At this location Gadolinite-(Y) is quite common and can also be found today. From this location the largest Austrian Gadolinite is known, it is a perfect xtl with about 1,5cm and has been found by Roland Winkler! However the location is really small even today Gadolinite can be found. The last found I know is only one week ago. (Information received from Martin Slama-2009).
I have treated these two localities as one location in this article due to their geological and geographical proximity. According to the Mindat locality pages, the mineralization at the Moos location is in the same rock formation as the Municipality Quarry. I find it quite interesting though that both gadolinite species are found within such a small area.
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Ce
USA
Washington, Okanogan Co, Golden Horn Batholith, Washington Pass
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| gadolinite-Ce | © Saul Krotki 2009 |
The Golden Horn batholith is a quite recent (~45 mill years) alkaline granite enriched in REE. The gadolinite is found as small (mm sized) brownish crystals in miarolic cavities in the rock. Several great location photos from the area are uploaded to mindat.
In another thread on refering to a gadolinite crystal from this location, Saul Kroti ( 2009) states the following:
"This gadolinite, was found to be metamict, and required gradual recrystallization by annealing for forty-eight hours at 700˚ C, before a distinct diffraction pattern could be obtained. Accomplished by John Attard, December 2008, the pattern matched gadolinite-(Ce) Type material from the Bjørkehalen pegmatite, near Buer, Norway, reported by Segalstad and Larsen (1978).
In many samples the outer-most zones or encrustations are yttrium dominant, (in 8 fold coordination), but in the inner cores Ce dominates Y by a large margin. I do not yet know how consistent this observation will prove to be. But that was so for thirty crystals examined.
Oscillatory zones with light and dark bands examined in polished thick section show only the most subtle variations of composition, not yet summarized. But in this specimen the texture is not what you find in the crystals with the dark and light bands which you see only by surprise in BSE/SEM, but not in photomicrography."
More information on this and/or similar locations will be highly appreciated.
Gadolinite-Ce
Norway
Telemark, Porsgrunn, Bjørkedalen, Buer
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| gadolinite-Ce | © Knut Eldjarn |
This is the type locality for gadolinite-Ce. The gadolinite-Ce crystals are found embedded in a syenite pegmatite of the same type as the famous Langesundfjord pegmatites. Gadolinite-Ce has also been found in a few other pegmatites in the area. The crystals are black and metamict amorph. More information on this and/or similar locations will be highly appreciated.
More information on this and/or similar locations will be highly appreciated.
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Edited 24 time(s). Last edit at 03/25/2012 01:56AM by Rock Currier.
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Re: Gadolinite August 13, 2009 07:40PM |
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Re: Gadolinite August 13, 2009 07:55PM |
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Re: Gadolinite August 13, 2009 08:24PM |
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Re: Gadolinite August 14, 2009 01:49AM |
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Re: Gadolinite August 16, 2009 08:39PM |
Registered: 7 years ago Posts: 8,477 |
Olav,
I would like to upload an image of Gadolinite to Mindat, but am not sure what locality to put it under. The specimen is one I took a picture of in 1975 in the British Museum and the label said Saetersdalen, Norway. Dalen appears to be a common ending for localities there, but I can find nothing with Sateters in the front. Perhaps you can help with this.
Rock Currier
Crystals not pistols.
I would like to upload an image of Gadolinite to Mindat, but am not sure what locality to put it under. The specimen is one I took a picture of in 1975 in the British Museum and the label said Saetersdalen, Norway. Dalen appears to be a common ending for localities there, but I can find nothing with Sateters in the front. Perhaps you can help with this.
Rock Currier
Crystals not pistols.
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Re: Gadolinite August 16, 2009 10:27PM |
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Registered: 7 years ago Posts: 85 |
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Re: Gadolinite August 17, 2009 08:03PM |
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Registered: 7 years ago Posts: 513 |
Rock,
The specimen from British museum is from one of the quarries in the Evje/Iveland area. The name Dalen means Valley. The Setesdalen valley is a 200+km long valley, but it is only some of the granite pegmatites in the Evje/Iveland area that carries gadolinite. Which one of the quarries is impossible to know.
I think that this must be one of the early finds early 1900-hundred, and that it originally probably was labeled Nedre Setesdalen ( Lower Setesdal valley) and that the administrative borders and names has changed since then. Therefore the locality label seems a bit haphazard today.
The specimen from British museum is from one of the quarries in the Evje/Iveland area. The name Dalen means Valley. The Setesdalen valley is a 200+km long valley, but it is only some of the granite pegmatites in the Evje/Iveland area that carries gadolinite. Which one of the quarries is impossible to know.
I think that this must be one of the early finds early 1900-hundred, and that it originally probably was labeled Nedre Setesdalen ( Lower Setesdal valley) and that the administrative borders and names has changed since then. Therefore the locality label seems a bit haphazard today.
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Re: Gadolinite August 19, 2009 07:00PM |
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Registered: 7 years ago Posts: 1,306 |
Olav,
Nice start on a Gadolinite article.
Just a corrections: The Gadolinite-Y Xl from Hundholmen in Tysfjord is 1,5 cm as stated in the text of the photo in Mindat.
As to the text for Hundholmen you might write:
"The Hundholmen pegmatite is one of the largest and most mineral rich of a number of granite pegmatites in the Tysfjord area of Northern Norway. The pegmatites are rich in REE-minerals. Gadolinite-Y has been found in some of the pegmatites mainly in the border zone of large masses of yttrian Fluorite and as grains embedded in the yttrian fluorite.Good crystals to several mm have also been found and more rarely at the Hundholmen pegmatite larger and well formed crystals to about 1,5 cm are known. The Gadolinite-Y from Hundholmen is bottle-green and non-metamict which is unusual for Gadolinites from REE-pegmatites."
Some of the largest and best crystals of Gadolinite-Y ever found come from the pegmatites of Hidra and large groups can be admired in the display of the Geological museum in Bergen. I hope you will get some pictures of those.
Knut
Nice start on a Gadolinite article.
Just a corrections: The Gadolinite-Y Xl from Hundholmen in Tysfjord is 1,5 cm as stated in the text of the photo in Mindat.
As to the text for Hundholmen you might write:
"The Hundholmen pegmatite is one of the largest and most mineral rich of a number of granite pegmatites in the Tysfjord area of Northern Norway. The pegmatites are rich in REE-minerals. Gadolinite-Y has been found in some of the pegmatites mainly in the border zone of large masses of yttrian Fluorite and as grains embedded in the yttrian fluorite.Good crystals to several mm have also been found and more rarely at the Hundholmen pegmatite larger and well formed crystals to about 1,5 cm are known. The Gadolinite-Y from Hundholmen is bottle-green and non-metamict which is unusual for Gadolinites from REE-pegmatites."
Some of the largest and best crystals of Gadolinite-Y ever found come from the pegmatites of Hidra and large groups can be admired in the display of the Geological museum in Bergen. I hope you will get some pictures of those.
Knut
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Re: Gadolinite August 19, 2009 07:52PM |
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Re: Gadolinite August 19, 2009 08:09PM |
Registered: 6 years ago Posts: 39 |
Hi Olav,
the Municipial quarry in Böckstein/Austria is long time abandoned and there is only one cleft with Gadolite in the left corner of the quarry. Some people have found Gadolinite in the last years, I have found my only Gadolinite in 2007. Intersting at the Municipial quarry is that the Gadolinite xls are mostly well terminated and not metamict. Most Gadolionite xls are associated with Muskovite, Chlorite, well terminated Aeschynite-(Y) and Titanite, sometimes with Rutile or Brookite.
In your article I`m missing another important localiyt where Gadolinite have been found, it is the location called "Moos" which is located about 150m behind the Municipial quarry. At this location Gadolinite-(Y) is quite common and can also be found today. From this location the largest Austrian Gadolinite is known, it is a perfect xtl with about 1,5cm and has been found by Roland Winkler! However the location is really small even today Gadolinite can be found. The last found I know is only one week ago.
the Municipial quarry in Böckstein/Austria is long time abandoned and there is only one cleft with Gadolite in the left corner of the quarry. Some people have found Gadolinite in the last years, I have found my only Gadolinite in 2007. Intersting at the Municipial quarry is that the Gadolinite xls are mostly well terminated and not metamict. Most Gadolionite xls are associated with Muskovite, Chlorite, well terminated Aeschynite-(Y) and Titanite, sometimes with Rutile or Brookite.
In your article I`m missing another important localiyt where Gadolinite have been found, it is the location called "Moos" which is located about 150m behind the Municipial quarry. At this location Gadolinite-(Y) is quite common and can also be found today. From this location the largest Austrian Gadolinite is known, it is a perfect xtl with about 1,5cm and has been found by Roland Winkler! However the location is really small even today Gadolinite can be found. The last found I know is only one week ago.
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Re: Gadolinite August 19, 2009 08:45PM |
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Registered: 7 years ago Posts: 1,306 |
Olav,
I probably have most of the publications you may be looking for concerning the Norwegian pegmatites with Gadolinite-Y and have consulted a few of them.
Gadolinite-Y in rough crystals to about 10 cm - sometimes covered by Muscovite - are not uncommon in the Li-bearing pegmatites in Tørdal (Høydalen) in Telemark. Sharp crystals to a few cm are known from a pegmatite in Fyrrisdal. Gadolinite is uncommon in the many pegmatites along the coast from Bamble to Kristiansand and I have seen no good crystals. A brownish, Ca-rich Gadolinite- Y occur at the Karlstadgangen pegmatite but only poorly crystalized. Gadolinite is known from pegmatites inland from Arendal ( i.e. at Froland). The pegmatites on the island of Hidra in Vest-Agder was worked in the 19th century and some of them produced large and spectacular crystals of Gadolinite to more than 30 cm (especially Urstad and Igletjern).
Knut
Edited 1 time(s). Last edit at 08/19/2009 09:27PM by Knut Eldjarn.
I probably have most of the publications you may be looking for concerning the Norwegian pegmatites with Gadolinite-Y and have consulted a few of them.
Gadolinite-Y in rough crystals to about 10 cm - sometimes covered by Muscovite - are not uncommon in the Li-bearing pegmatites in Tørdal (Høydalen) in Telemark. Sharp crystals to a few cm are known from a pegmatite in Fyrrisdal. Gadolinite is uncommon in the many pegmatites along the coast from Bamble to Kristiansand and I have seen no good crystals. A brownish, Ca-rich Gadolinite- Y occur at the Karlstadgangen pegmatite but only poorly crystalized. Gadolinite is known from pegmatites inland from Arendal ( i.e. at Froland). The pegmatites on the island of Hidra in Vest-Agder was worked in the 19th century and some of them produced large and spectacular crystals of Gadolinite to more than 30 cm (especially Urstad and Igletjern).
Knut
Edited 1 time(s). Last edit at 08/19/2009 09:27PM by Knut Eldjarn.
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Re: Gadolinite August 23, 2009 06:47AM |
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Registered: 7 years ago Posts: 513 |
Martin,
Thank you very much for the input on the Austrian locations. I have grouped the Municipality quarry and the Moos location into one entry. I hope that is OK with you? Do you, or anyone else, have the opportunity to get a photo of the 1,5cm crystal from Moos? That would be awesome and would improve the article a lot.
Knut, Your knowledge and experience is invaluable.
Also Aksel Österlöf has reminded me of the gadolinites of the Routevarre pegmatite. Ha has already sent me an extensive paper on this pegmatite and I am surely to blame for not remembering what I've read just a few weeks ago. I'll include it. I don't have time right now.
For the two articles I have wrote so far I am just throwing myself into it, and I am totally dependant on the knowledge and experience of you all, both for filling in all my blanks, but also to provide QC on the stuff that I write.
Thank you very much for the input on the Austrian locations. I have grouped the Municipality quarry and the Moos location into one entry. I hope that is OK with you? Do you, or anyone else, have the opportunity to get a photo of the 1,5cm crystal from Moos? That would be awesome and would improve the article a lot.
Knut, Your knowledge and experience is invaluable.
Also Aksel Österlöf has reminded me of the gadolinites of the Routevarre pegmatite. Ha has already sent me an extensive paper on this pegmatite and I am surely to blame for not remembering what I've read just a few weeks ago. I'll include it. I don't have time right now.
For the two articles I have wrote so far I am just throwing myself into it, and I am totally dependant on the knowledge and experience of you all, both for filling in all my blanks, but also to provide QC on the stuff that I write.
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Re: Gadolinite August 24, 2009 07:10PM |
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Registered: 7 years ago Posts: 513 |
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Re: Gadolinite August 24, 2009 10:07PM |
Registered: 7 years ago Posts: 8,477 |
Olav, Each caption should start with the name of the species in the image. Also make sure your localities above the images are in reverse locality order. When you take care of this, Ill come in and work a little more on the formatting to bring it more in line with our current standards.
Rock Currier
Crystals not pistols.
Rock Currier
Crystals not pistols.
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Re: Gadolinite August 26, 2009 01:45AM |
Registered: 5 years ago Posts: 26 |
Hi Olav, the geologic description is correct, respect the gadolinite of the Schrammacher Mt.
In the discussion I add another place that is the Vizze Pass and it is near to the preceding one where I have found the gadolinite in small but well formed crystals of quality it gemmates.
Unfortunately also in this place as in that preceding they are very rare, but at times looking for with some fortune they are found.
The rock is always metamorphic and more precisely an quartzporphyr in a conglomerate gneiss absorbed.
Very interesting the fact that is the same fissure mineralized where the genthelvite and others rare mineral is found.
Ciao.
[www.mindat.org]
[www.mindat.org]
In the discussion I add another place that is the Vizze Pass and it is near to the preceding one where I have found the gadolinite in small but well formed crystals of quality it gemmates.
Unfortunately also in this place as in that preceding they are very rare, but at times looking for with some fortune they are found.
The rock is always metamorphic and more precisely an quartzporphyr in a conglomerate gneiss absorbed.
Very interesting the fact that is the same fissure mineralized where the genthelvite and others rare mineral is found.
Ciao.
[www.mindat.org]
[www.mindat.org]
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Anonymous User
Re: Gadolinite August 26, 2009 03:06AM |
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Re: Gadolinite August 26, 2009 06:25AM |
Registered: 6 years ago Posts: 39 |
Hi Olav,
for me it is ok when you describe the Municipial quarry and Moos together. The large Gadolinite was found by Roland Winkler and has been published in the Lapis Magazine years ago (Lapis Magazine November 2003). I don`t hae the elder Magazines but I try to get it.
Edited 1 time(s). Last edit at 08/26/2009 06:32AM by Martin Slama.
for me it is ok when you describe the Municipial quarry and Moos together. The large Gadolinite was found by Roland Winkler and has been published in the Lapis Magazine years ago (Lapis Magazine November 2003). I don`t hae the elder Magazines but I try to get it.
Edited 1 time(s). Last edit at 08/26/2009 06:32AM by Martin Slama.
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Re: Gadolinite August 26, 2009 03:06PM |
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Registered: 7 years ago Posts: 513 |
To all,
Thanks for your fantastic input for this article. I will not have the time to update it the next week or so I think, but the upcoming work are:
- update the Moos location with the article reference and where the big one is located
- include the Vizze pass and the White cloud pegmatite as new location.
- include [www.mindat.org], with this: [www.mindat.org]
- Expand the description of the Ytterby and Hidra locations based additional information.
- include photo(s) from the Hidra pegmatites
If possible, include more information on the scientific work based on gadolinite from Ytterby and Hidra.
A special thanks to Jim for introducing an American locality The US has 2 pages of listed localities. Some of them must have produced quality specimens.
Again, Thank you so much for your amazing and great input. I am learning so much from this work. Thanks again.
Thanks for your fantastic input for this article. I will not have the time to update it the next week or so I think, but the upcoming work are:
- update the Moos location with the article reference and where the big one is located
- include the Vizze pass and the White cloud pegmatite as new location.
- include [www.mindat.org], with this: [www.mindat.org]
- Expand the description of the Ytterby and Hidra locations based additional information.
- include photo(s) from the Hidra pegmatites
If possible, include more information on the scientific work based on gadolinite from Ytterby and Hidra.
A special thanks to Jim for introducing an American locality The US has 2 pages of listed localities. Some of them must have produced quality specimens.
Again, Thank you so much for your amazing and great input. I am learning so much from this work. Thanks again.
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Re: Gadolinite August 27, 2009 11:10AM |
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Registered: 7 years ago Posts: 10,064 |
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