Actinolite

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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?


Actinolite Display collections.
□Ca₂(Mg,Fe²⁺)5Si₈O₂₂(OH)₂


A terminated gemy actinolite crystal from Mogok, Sagaing District, Mandalay Division, Burma (Myanmar). Specimen is 4.9 cm high.

Actinolite is a calcium magnesium iron hydroxy silicate. It forms a series with tremolite and ferroactinolite and it is probable that at least some of the actinolites described here may not be strictly actinolite but rather tremolite. Alfredo Petrov says "I know the name "actinolite" has a long history but, technically, it's an iron-rich Tremolite, so this discussion should be taken out of the "A"s and moved to the "T"s. For the practical purposes of these articles, unless the identification smells completely fishy, we accept the identification of the person uploading the images. We hope that people with a real knowledge of actinolite from various localities will step forward and help correct any mistakes we have made. As Knut Eldjarnit, one of our contributors observes "...it should be important to decide to what extent your article will also cover Ferroactinolite or unanalyzed dark "Actinolites" which could be one or the other." He also wisely observes "Actinolite is very common in Scandinavia and specimens rivalling many of the ones you have pictured and described are to be found in local mineral collections from probably hundreds of different localities. Actinolite is one of those common minerals where specimens seem to disseminate in a local or regional "market" or mostly as self-collected specimen. A number of the US localities you decribe will be unknown to European and Scandinavian collectors, just as a number of important localities here will never produce specimens for the US collector market." He goes on to suggest that we might consider organizing the actinolites described her in terms of their paragenetic environment such as
1. Contact metemorphic localities and skarn
2. Regional metamorphic localities
3. Alpine type veins
4. Miarolitic cavities in granites and other igneous rocks
This is not an unreasonable idea, but until he or someone may care to undertake such a task we will continue with our simple minded description of the "Best" actinolites, alphabetically by country. It can therefore be a bit tricky to find the right criteria for localities to be included in the article. This will undoubtedly also be true for other parts of the world.

Actinolite occasionally forms good crystals, but most of the time it doesn’t. You see a lot of not very exciting actinolite specimens in collections, often drawers full of them in big institutional collections and look in vain for one that is exciting. Most of them are greenish prismatic crystals embedded in other minerals or intergrown masses of greenish crystals. It is almost as though the mineral doesn't want to form good terminations. Mindat list over 1600 localities and undoubtedly there are many more only of which only a small fraction of them will end up being described in this article.

There are compact massive forms of actinolite that are often called nephrite jade and this material can often be cut into rather attractive cabochons that are often used for jewelry purposes. Sometimes this mineral is found in intergrown, olive green, hair like masses and is called byssolite. I am always suspicious that some of these specimens may not be actinolite but perhaps tremolite or some other mineral. Often you will see quartz crystals with green hair like inclusions that is labeled actinolite in quartz. It is much easier to put an actinolite label on such specimens rather than confirm the identification by analysis. In the polar Urals, Russia, there was apparently a walk-in sized pocket lined with quartz crystals and fabulous axinite specimens that was stuffed full in places with fibrous green byssolite. Some of the byssolite had perfect small, two to three cm, gemmy, lustrous, floater ferroaxinite crystals in them. The miners would grab a handful of the byssolite and shake the axinites out. It would be great to have a handful of the stuff with the axinites still in it, but I doubt if any of it was saved.

Another variety of actinolite is the fibrous looking, olive green crystals called uralite that are actinolite pseudomorphs after augite, diopside and other minerals. There are many localities for this kind of actinolite. Yet another variety of actinolite is called mountain leather, which consists of densely matted inter-growths of microscopic, long fibrous crystals. These mats are usually whitish in color and you can bend them around a little like leather. A few other minerals like palygorskite and tremolite also form similar leather-like masses.

I have seen few good specimens of actinolite offered for sale. It is hard to imagine what a $1000 actinolite specimen might look like although the some gemmy crystals from Madagascar and especially Burma might easily bring that much.


Actinolite
Australia
Tasmania, Rosenbery District, Colbrook Hill, Colebrook Hill Mine



This is a locally well known location for axinite-(Fe),and next to this, tremolite-actinolite is the most common gangue mineral to be found at the site. White to bright green tremolite-actinolite occurs as radiating aggregates ("suns", fibrous mats (variety byssolite), pseudomorphs after diopside and ragged to fibrous crystals, up to 30 mm or so in length in this mine. Specimens of actinolite (with associated axinite) may range in size up to 30 by 60 cm and can be quite aesthetic, especially when there is a smattering of axinite on the actinolite, giving a contrast of the purple axinite against the green actinolite. Superb specimens of actinolite, associated with quartz, axinite and arsenopyrite, can still be found today at the Colebrook Mine, but are usually overlooked for axinite. Samples are usually etched from calcite.

The site is an abandoned underground copper mine, later open-cut, worked from about 1898 to 1917 in a number of lodes on the top of Colebrook Hill. It is now is a designated official fossicking area, and although permits are not required, collectors are advised to obtain information on rules, conditions, etc. before visiting the area. Access is largely steep, difficult and dangerous in parts, and it is not recommended for the unfit, and visitors should not attempt it alone. Not much significant has come from this old abandoned mine in recent years as the track has become impassable. On my last visit, we had to bash our way up the mountain through heavilly snake and leech infested swamp and rainforest (half the party did not make it). There is still a large dump with abundant low quality axinite and actinolite, but it really needs hard work and new exposures to produce good specimens.
[Ralph Botrill 2009]


Actinolite
Austria
Carinthia, Huttenberg area, Friesach, Hirt, Griesserhof (Gulitzen: Gullitzen), Serpentinite quarry




Actinolite (Var: Smaragdite)
Austria
Salzburg, Hohe tauern Mts, Habach Valley, Nasenkopf Mt., Leckbachgraben (Leckbachrinne), Emerald deposit



In the Talcum Schist surrounding the Emerald bearing Muscovite and Biotite Schists of the Leckbachrinne Actinolite is a very common mineral. Quite often the Actinolite occurs in a very appealing Emerald green colour, hence it's varietal name "Smaragdite" (Smaragd is the German word for Emerald) The local name for the Talcum containing Actinolite pieces is "Strahlstein" ("raystone" in English) and they can be found very easily in sometimes very large specimens.
[Harjo Neutkens]


Actinolite
Austria
Salsberg, Hohe Tauern Mts., Krimmler Ache valley, Söllnkar




Actinolite
Austria
Salsburg, Hohe Tauern Mts., Untersulzbach valley, Knappenwand area, Knappenwand.



This locality is much better known for its wonderful shiny prismatic epidote crystals which often occur with byssolite. Many specimens of matrix epidote crystals have been manufactures using broken off single crystals of epidote glued onto matrix and the fibrous green byssolite glued on the specimen to cover up the broken bottoms of the epidotes and to cover up the glue. These are classical fakes.
[Rock Currier, 11 January 2009]


Actinolite
Austria
Tyrol, East Tyrol, Virgen valley, Prägraten, Dorferbach valley.




Actinolite
Austria
Tyrol, North Tyrol, Ziller valley.

Actinolite, specimen 10 cm wide	© G. van der Veldt

Actinolite
Brazil
Bahia: Victória da Conquinsta District, Brumado

“The actinolite crystals reach a size of more than 25 cm in length and 2 cm in width, but generally contain transverse micro-fractures invaded by talc. They are of brilliant luster, light to dark green, and occur in groups and clusters without preferential orientation. Some crystals are curved. Large, attractive samples may be easily collected here.”₁ Not all of the actinolite found here has micro-fractures invaded by talc. Look at this cluster of shiny black terminated crystals up to at least 8 cm which was in the collection of Dr. Richard Gains. I would not mind owing one of these but I have not seen any for sale on many trips to Brazil nor while spending a week collecting in the magnesite mine at Brumado. I doubt that they were very expensive when they were first collected and sold.
1. Jacques & Jeannine Cassedanne, Mineralogical Record, May/June 1987 p204.


Actinolite
Brazil
Minas Gerais, Conselheiro Lafiaete (old Queluz de Minas)




Actinolite
Burma
Mandalay Division, Sagaing District, Mogok



Probably the best crystals of actinolite currently being produced are from this locality. We need someone to tell us more about them.


Canada
Ontario, Haliburton Co., Norland



Collected by Maggie Wilson 2010.


Actinolite
Canada
Ontario, Leeds and Greenville Co., Portland




Actinolite
Czech Republic
Moravia, Olomouc Region, Šumperk, Sobotín, Smrčina.




Actinolite
Finland
Lapin (Lapland) Lääni, Kemi, Elijärvi (Kemi) Cr mine




Actinolite
Finland
Lapin (Lapland) Lääni, Penikat complex, Sompujärvi Reef.




Actinolite
France
Midi-Pyrénées, Haute-Garonne, Sallies-du-Salat, Ophite Quarries




Actinolite
Italy
Aosta Valley, Courmayeur, Monte Bianco Massif, Veny Valley, Miage Glacier.

Actinolite var. byssolite, 12 cm across.	© luigi chiappino

Actinolite
Italy
Lombardy, Sondrio Province, Malenco Valley




Actinolite
Italy
Bolzano Province, Aurina valley, Selva dei Molini Valley (Mühlwald Valley)




Actinolite
Madagascar
I have seen a small 2 cm gem crystal from Madagascar in the collection of Ed Swoboda of Los Angeles and, if it is really actinolite, would be exceptional. It would have to be perhaps the best quality actinolite found so far. Undoubtedly there were better crystals that went under the cutters wheel in Madagascar. The locals cut anything that is transparent into gems even though they may not know exactly what it is they are cutting. I wish I had a better locality to give you and in fact I wish I could be sure that it is Actinolite. Certainly someone out there can tell me?
[Rock Currier, 2009]


Actinolite
Malawi
Zomba District, Mt. Malosa



Most of the black prismatic crystals from Mt. Malosa are aegirine. Probably the finest aegirine crystals in the world are from this locality. The actinolites are just a little cureousity from there compared to most of the other specimens.


Actinolite
Mexico
Zacatecas, Mun. de Concepción del Oro, Concepción del Oro




Actinolite
Morocco
Meknès-Tafilalet Region, Er Rachidia Province, High Atlas Mts, Imilchil




Actinolite
Namibia
Otjozondjupa Retion, Otjiwarongo District.

Actinolite, 6.1 cm tall	© Rob Lavinsky

Actinolite
New Zeland
South Island, Arahura Valley, Olderog Creek



An example of what can be made out of some types of actinolite that are massive and solid enough. We need someone to tell us something aobut the actinolite from this locality.


Actinolite
Norway
Aust-Agder, Vegårdshei (Vegårshei), Selåsvatn

Actinolite, 11.5 cm tall	© Peter Andresen

Actinolite crystals from this locality occurs as intergrown fans or stars of "needles". The individual crystal may exceed 7 cm in length, but are still rarely more than few mm thick. Actinolite has a strong shiny lustre, and the colour is a bright greyish green. The crystals are sometimes hairlike and intergrown in thick mats with an almost silk-like luster. Actinolite from Selåsvatn can be seen in Agder Naturmuseum and in the mineral collection of Aust-Agder Museet. Actinolite is abundant at the location, and most, if not all, local collectors have specimens from here. Here actinolite occurs with ankerite and dolomite in a quarry worked for quartz, and is formed in the contact between the carbonates and the quartz during regional metamorphosis. Actinolite is a common mineral in many calcsilicate rocks in the area, alltough rarely as good or abundant as at Selåsvatn. The location is NOT available for collectors anymore. "The locality at Selåsvann was worked extensively for specimens by then mineral dealer Gunnar Raade in the late 1960`ies and a number of also large specimens were sold to collectors and museums in Europe."¹
1. Knut Eldjarn, email 2009.
[Olav Revheim 2009]


Actinolite
Norway
Aust-Agder, Risør, Søndeled,

During road work on E 18 at Søndeled, Risør, Aust-Agder in 2002/2003 a system of large cavities with excellent Diopside crystals to more than 10 cm were encountered. The Diopside crystals have an epitaxial overgrowth of scattered well developed 5 mm thick individual crystals of Actinolite to about 2 cm. These showy and mineralogically very interesting specimens can be seen in museum displays and private collections in Norway and they were also for a short periode available on the European mineral market through Italian and German dealers. Larger, single crystals of Actinolite were also found and a huge crystal is on display at the Kongsberg Mineral Museum. This locality is in the Kongsberg-Bamble geological province which harbours many good localities for Actinolite. For example localities in the vicinity of Kragerø, Telemark, i.e. at Langøya, have produced large aggregates of green Actinolite-needles to 5 cm partly growing on white crystals of Albite and partly embedded in clear Calcite. We hope that someone will upload some images of these specimens so that we can include them in this article.
[Knut Eldjarn, 2009]


Actinolite
Norway
Nordland, Rana, Mo i Rana area, Altermark Talc Mine

Actinolite & Talc, 15 cm wide	© Olav Revheim

Actinolite, specimen is about 8 cm across.	© Olav Revheim

The Altemark Talc mine is well known for it's actinolite crystals. The actinolite cn be found as individual crystals or as crystal fans in talc. The crystals can reach a length of at least 10cm. The best crystals are partly transparant and has a very nice green color, due to traces of chromium. The occurance of actinolite is remarkably consistant throughout the location. A large number of specimens are found at the mine dump of the location. The crystals are found in the border zone between a talc rock and the surrounding rocks. The mineralization is a result of metamorphic actions on an ultramafic body with a 200m diametre. The rocks follow a clear zoning, with ultramafic rocks in the centre, serpentinite, a talc/carbonate rock, a transition zone and finally the surrounding mica schists/marbles and amfibolites. In carbonate rich zones nice magnesite crystals can be found. The actinolites are very brittle and trimming of specimens should be performed with care. The value of these actinolites are not sufficient for anyone to make fakes. "The locality at Altemark has been producing excellent specimens of Actinolite crystals in Talc for more than 50 years. I visited and collected at the locality the first time in 1964. The locality is paragentically very similar to many other localities you describe in your draft article and specimens also resemble specimens from similar metamorphic environments in other parts of the world.¹
1. Knut Eldjarn, email 2009.
[Olav Revheim 2009]


Actinolite
Norway
Oppland, Lunner, Grua, Grua Tunnel

Excellent "uralite" pseudomorphs of Actinolite after Diopside with crystals to 10 cm were found in the railroad tunnel south of Grua stasjon, Lunner, Oppland, Norway by the railroad construction engineer J. Kvam in 1902. Specimens can be seen on display in Scandinavian and other European museums and in old private collections. The locality and crystals were described in detail by V.M. Goldschmidt in his classic work "Die Kontaktmetamorphose im Kristianiagebiet" (Vit.Ak.Skrft. I, 1911, no. 11, Jacob Dybwad, Kristiania 1911). We hope that someone will upload a few pictures of these specimens so that we can include them here.
[Knut Eldjarn, 2009]


Actinolite
Pakistan
Northern Areas, Baltistan, Skardu District, Shigar Valley, Alchuri (Alchori; Aschudi)




Actinolite
Poland
Lower Silesia (Dolnośląskie), Gogołów-Jordanów Massif, Jordanów (Jordansmühl)




Actinolite
Portugal
Leiria District, Leira, Monte Redondo, Montkjos Quarry

Actinolite specimen 12 cm across	© Martins da Pedra

At the dolerite quarries of about 150 km north of Lisbon near Monte Redondo are found pockets up to about 30 cm. Some pockets contain masses of dark green to black randomly oriented networks of actinolite crystals up to about 15 cm. The crystals are very thin, but thick enough so that they will not bend like the thinner hair like variety called byssolite. These specimens are very delicate and difficult to transport. A number of fine specimens from this locality are located in the mineral museum of the Technical University at Porto. See the good article on this locality by Richard Gaines.₁
1 Mineralogical Record, Jan/Feb 1971 p41+.


Actinolite
Russia
Eastern-Siberian Region, Saha Republic (Sakha Republic; Yakutia), Aldan Shield

This nephrite variety of actinolite is hard enough and colorful enough that it is in demand by cutters to make jewelry and other lapidary items. The locality is prolific. Experiments have been made to make the dark material in the deposit a lighter color and were successful. I don't know if it will be applicable to commercial operations. The state run Russian company just outside of Irkutsk used large boulders of this material from which to make a good variety of attractive lapidary articles like bowls and vases. They used two meter diamond saws to but these boulders and diamond core drills to drill out cylinders from which bowls and vases could be turned using other diamond tooling. The last I heard, the company had fallen on hard times and production was very low or non existent.
[Rock Currier 2009]


Actinolite
Spain
Valencian Community, Alicante, Albatera, Hondón de los Frailes, Los Serranos Quarry




Actinolite
Switzerland
Wallis (Valais), Lötschen valley.




Actinolite
USA
Alaska Prince of Wales Island, Sulzer



Pictured here is a cluster of actinolite pseudomorphs (uralite) probably after a pyroxene group mineral from Prince of Wales Island. The crystals approach 3 cm in size. The group labeled Sulzer is probably from the same locality. Such specimens, when sold at gem and mineral shows do not bring very much money. This specimens would probably not bring more than $50.


Actinolite
USA
California, Los Angeles, Wrightwood

At Wrightwood, there is a locality in the San Bernardino Mountains that has produced tons of good study grade actinolite specimens consisting of densely inter-grown non terminated greenish crystals that no collector in his right mind would put in his collection. When faced with nice specimens of such material lying all over the ground, a collector finds himself picking up some of them and putting them in his car even though they have no possible use for them except to decorate a planter or their his garden.


Actinolite
USA
Colorado, Chaffee County, Turret District, Calumet Iron Mine



These specimens have been dribbling out for years and there are hundreds of them scattered through collections around the world. We need someone to tell us more about these specimens.


Actinolite
USA
Vermont, Windsor Co., Chester




Actinolite
USA
Virginia, Fairfax Co., Culpeper Basin, Centerville, Fairfax quarry



The quarry is much better known for its specimens of apophyllite on prehnite. In the big pocket where most of the good prehnite and apophyllite specimens were found, there was a lot of byssolite. One of the diggers told me that growing loose in the byssolite were complete balls of prehnite, some of which were heavily included with the actinolite and when the matrix pieces were pulled from the pocket, they would turn the specimens over and shake out the balls of prehnite that were in the byssolite. The problem with all byssolite specimens is that they are so delicate that few of them survive any length of time.


Actinolite
USA
Washington, Chelan Co. Lake Wenatchee, Wenatchee Ridge

Actinolite, 5.5 cm across.	© Alan Goldstein

The largest crystals I know of occur far down on the South side of Wenatchee Ridge at a site held by non-patented mining claims for specimens by various mineral clubs, and, at one time by Jack Zektzer. Crystals 2.5 inches by 6 inches have been collected.¹. The actinolite from Washington, Chelan Co. Lake Wenatchee, Wenatchee Ridge occurs as metasomatized pods within an orthogneiss. The Orthogneiss was a tonalite that has also been intruded by tonalitic dikes that are high-pressure dikes and pegmatitic in places. The pods are thought to be scraps of utra-mafic oceanic crust that got caught up in the emplacement of the tonalite (see articles by Tabor). There are outcrops of the ultramafic rocks over a kilometer along strike and many meters thick within Wenatchee Ridge. The pods are commonly zoned with chlorite/phlogopite along their borders grading into talc-actinolite cores, although the actinolite is also commonly embedded in the chlorite.
1. Bart Cannon (The Minerals of Washington, Cannon), email communication. I am amazed and delighted that he would come up out of his microprobe infested basement long enough to contribute to our effort here.
[Ian Merkel, 2009]



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Rock Currier
Crystals not pistols.



Edited 74 time(s). Last edit at 03/25/2012 06:55AM by Olav Revheim.

Actinolite
Norway
Aust-Agder, Vegårdshei (Vegårshei), Selåsvatn

Actinolite crystals occurs as intergrown fans or stars of "needles". The individual crystal may exceed 7 cm in length, but are still rarely more than few mm thick. Actinolite has a strong shiny lustre, and the colour is a brith greyish green. The crystals are sometimes hairlike and intergrown in thick mats with an almost silk-like lustre.

Actinolite from Selåsvatn can be seen in Agder Naturmuseum and in the mineral collection of Aust-Agder Museet. Actinolite are abundant at the location, and most, if not all, local collectors have specimens from here. Actinolite occurs with ankerite and dolomite in a quarry worked for quartz, and is formed in the contact between the carbonates and the quartz during regional metamorphosis. Actinolite is a common mineral in many calcsilicate rocks in the area, alltough rarely as good or abundant as at Selåsvatn.

The location is NOT available for collectors anymore

I have uploaded a cuple of photos aswell, from self collected specimens from 2002.
see links:

[www.mindat.org]
[www.mindat.org]
[www.mindat.org]

Dear Olav,
Thanks for the information about the actinolite locality at Selåsvatn. I have added it to the article and it has helped the article. Now we just need a few thousand others to step forward like you and help. Would you like to write up another mineral from another locality?

Rock Currier
Crystals not pistols.

The Altemark Talc mine is well known for it's actinolite crystals. The actinolite cn be found as individual crystals or as crystal fans in talc. The crystals can reach a length of at least 10cm. The best crystals are partly transparant and has a very nice green color, due to traces of chromium. The occurance of actinolite is remarkably consistant throughout the location. A large number of specimens are found at the mine dump of the location, and I found representative specimens of the mineral on both my visits.

The crystals are found in the border zone between a talc rock and the surrounding rocks. The mineralization is a result of metamorphic actions on an ultramafic body with a 200m diametre. The rocks follow a clear zoning, with ultramafic rocks in the centre, serpentinite, a talc/carbonate rock, a transition zone and finally the surrounding mica schists/marbles and amfibolites. In carbonate rich zones nice magnesite crystals can be found. How do they compare to other specimens of the same mineral from other localities?

The actinolites are very brittle and trimming of specimens should be performed with care.

The value of these actinolites are not sufficient for anyone to make fakes.

I've added a few photos:

[www.mindat.org] - actinolite
[www.mindat.org] - magnesite
[www.mindat.org] - talc

Olav, Thanks for the good information on the actinolite from the Altemark Talc mine. It has been incorporated into the actinolite article as you can see. It is now a better article thanks to your help.

Rock Currier
Crystals not pistols.

Hello Rock,

After Alabandite I see you have taken on the huge project of writing about "Actinolite" which forms series with both Tremolite and Ferroactinolite. The distinction to Tremolite is probably not that difficult, but it should be important to decide to what extent your article will also cover Ferroactinolite or unanalyzed dark "Actinolites" which could be one or the other.
As for Norwegian localities, I can add to the information from Olav Revheim:


The locality at Altemark has been producing excellent specimens of Actinolite crystals in Talc for more than 50 years. I visited and collected at the locality the first time in 1964. The locality is paragentically very similar to many other localities you describe in your draft article and specimens also resemble specimens from similar metamorphic environments in other parts of the world.

The locality at Selåsvann was worked extensively for specimens by then mineral dealer Gunnar Raade in the late 1960`ies and a number of also large specimens were sold to collectors and museums in Europe.

Actinolite is very common in Scandinavia and specimens rivalling many of the ones you have pictured and described are to be found in local mineral collections from probably hundreds of different localities. Actinolite is one of those common minerals where specimens seem to disseminate in a local or regional "market" or mostly as self-collected specimen. A number of the US localities you decribe will be unknown to European and Scandinavian collectors, just as a number of important localities here will never produce specimens for the US collector market. It can therefore be a bit tricky to find the right criteria for localities to be included in the article. My suggestion to you would be to organize the article in sections based on the paragenetic environment. In each section you could start with the localities that may have produced the best or most plentiful number of specimens for mineral collectors in general (reaching the "international market"). Further down in each section you may mention similar localities where the dissemination of specimens may have been more limited. We should probably work on such a classification of Actinolite localities, but a starting point could be:

1. Contact metemorphic localities and skarn
2. Regional metamorphic localities
3. Alpine type veins
4. Miarolitic cavities in granites and other igneous rocks

You can probably add some more and refine the classification.

There are important Norwegian localities not mentioned in your article:

Excellent "uralite" pseudomorphs of Actinolite after Diopside with crystals to 10 cm were found in the railroad tunnel south of Grua stasjon, Lunner, Oppland, Norway by the railroad construction engineer J. Kvam in 1902. Specimens can be seen on display in Scandinavian and other European museums and in old private collections. The locality and crystals were described in detail by V.M. Goldschmidt in his classic work "Die Kontaktmetamorphose im Kristianiagebiet" (Vit.Ak.Skrft. I, 1911, no. 11, Jacob Dybwad, Kristiania 1911).

During road work on E 18 at Søndeled, Risør, Aust-Agder in 2002/2003 a system of large cavities with excellent Diopside crystals to more than 10 cm were encountered. The Diopside crystals have an epitaxial overgrowth of scattered well developed 5 mm thick individual crystals of Actinolite to about 2 cm. These showy and mineralogically very interesting specimens can be seen in museum displays and private collections in Norway and they were also for a short periode available on the European mineral market through Italian and German dealers. Larger, single crystals of Actinolite were also found and a huge crystal is on display at the Kongsberg Mineral Museum. This locality is in the Kongsberg-Bamble geological province which harbours many good localities for Actinolite. For example localities in the vicinity of Kragerø, Telemark, i.e. at Langøya, have produced large aggregates of green Actinolite-needles to 5 cm partly growing on white crystals of Albite and partly embedded in clear Calcite.

Good crystals of Actinolite are also common in many of the skarn localities in the old mining district of Bergslagen in central Sweden. Excellent specimens can be seen in museums and private collections, especially in Sweden.

God luck with your project.

Knut

Knut,
Your thread posting has a lot of good observations and information that I will try and work into the actinolite article. To try and organize it in the way you suggest, is a great idea. Would you want to try and undertake the work? I fear that it might be beyond my abilities to do it all. As you point out there is a lot of actinolite and related species in the world and somehow we will have to make some decisions about what to include or not to include. I am still trying to figure out what to do about quartz. The practical criteria that I have used thus far is that if there is a decent picture of a significant specimen of the stuff here on mindat, then it gets included. Sometimes however there is no picture, but the locality is obviously too important to leave out, so I at least put a little something about it the article, with the expectation that sometime a picture will be forthcoming. Obviously localities that have produced lots of specimens that have found their way into many collections must be included.

Rock Currier
Crystals not pistols.

Hello Rock,

I will look into it, but there are many other pressing matters here in the coming days. As for your concern about Quartz, you still have a long way to go before you get to the letter Q. That will probably give you time to find a solution to the problem...

Cheers
Knut

Knut:
I certainly understand about other pressing matters. I am also going to have to take a break from this. I like you have only so much time do devote to this thing. It can eat up your life if you let it. But as time permits Ill incorporate much of your good information into the actinolite article.
Rock



Edited 1 time(s). Last edit at 03/15/2009 11:51PM by Rock Currier.

I would have called some of these specimens tremolite from the colour (eg Switzerlans, Virginia, etc), but perhaps they have all been analysed? Or perhaps the IMA will eventually bite the bullet and decide actinolite really is just Fe-bearing tremolite?
Ralph

Regards,
Ralph

Rock,

The actinolite from Washington, Chelan Co. Lake Wenatchee, Wenatchee Ridge occurs as metasomatized pods within an orthogneiss. The Orthogneiss was a tonalite that has also been intruded by tonalitic dikes that are high-pressure dikes and pegmatitic in places. The pods are thought to be scraps of utra-mafic oceanic crust that got caught up in the emplacement of the tonalite (see articles by Tabor). There are outcrops of the ultramafic rocks over a kilometer along strike and many meters thick within Wenatchee Ridge. The pods are commonly zoned with chlorite/phlogopite along their borders grading into talc-actinolite cores, although the actinolite is also commonly embedded in the chlorite.

Cheers,
Ian Merkel

P.s. what about the Chester Vermont locality? I believe it was called the Carlton MIne, which was a talc mine.

Knut,
I have incorporated most of your observations and information into the actinolite article and it is all the better for it. I have also changed out all the images for the new style images that include the copyright information down in the caption area. Hope you can find the time to help generate the content on some of the minerals not yet started. After all there are only about 4000 of them left to go. Better hurry up before they are all gone!

Rock Currier
Crystals not pistols.



Edited 1 time(s). Last edit at 04/11/2009 11:51PM by Rock Currier.

Ian,
Thats good information about the actinolite from Wenatchee Ridge and I have incorporated it into the actinolite article. Can you give us some idea how big the crystals get and how abundant the specimens from there are? What the best one(s) might look like?

I have also added the Chester, Vermont locality and hopefully someone will step up and tell us something about it. I think I saw it when I was going through the actinolite pictures, but just blew past it and it took someone like you to goad me into including it.

Rock Currier
Crystals not pistols.



Edited 1 time(s). Last edit at 03/16/2009 09:38AM by Rock Currier.

Ralf and Knut raise a point that has been worrying me. By focussing on species we can miss the connections between them, especially with series, but more generally with groups. In response, this is a best stuff forum and not a classification forum. We have that elsewhere. Further in the general Blurb at the top of the string one can put in something about relations to other species. I have yet to do this for polybasite, at least from Husky.

Bob, Yes that is exactly what I envision. There will be a general discussion at the top of mineral thread for each mineral where relationships between the mineral the forum is about and other minerals can and should be discussed. You will note that I have added these kinds of comments at the top of the actinolite forum.

Rock Currier
Crystals not pistols.

There are a dozen or so notable actinolite occurrences in the Wenatchee Lake area.

The largest crystals I know of occur far down on the South side of Wenatchee Ridge at a site held by non-patented mining claims for specimens by various mineral clubs, and, at one time by Jack Zektzer. Crystals 2.5 inches by 6 inches have been collected.

I know the name "actinolite" has a long history but, technically, it's an iron-rich Tremolite, so this discussion should be taken out of the "A"s and moved to the "T"s.
)

I agree that Actinolite is merely an iron rich tremolite, but the IMA in its infinite wisdom has grandfathered it. This will protect the species status of actinolite until the IMA come to their senses and get rid of grandfathering or until a Pro can get them to accept a redefinition. So Actinolite should stay in the A's for now. If we deviate from IMA doctrine there will be no agreed understanding, conservatives will get angry, and Mindat would loose credibility. E,g should epidote be called an iron rich Clinozoisite because that gives the relation to Zoisite or should we call it an Iron deficient Epidote because Epidote is older and more common. (Yes I know the are two metal sites for the Iron and more than 50% generates a Species. Compare this to the site lumping in Amphiboles, Tetrahedrite, etc.!!!)

Since the Pros won't eat their young, I've come to the point where I regard the Groups as sufficiently different to be the real species and the Species with hair splitting differences that can only be observed with $100 grand machines are really just the varieties. Before you jump on me and say it's rediculous to have Zeolite as a a single Species, I only suggest this as first approximation to bringing some sanity back to nomenclature. The devil is clearly in the details.

Actinolite (Var: Smaragdite)
Austria
Salzburg, Hohe tauern Mts, Habach Valley, Nasenkopf Mt., Leckbachgraben (Leckbachrinne), Emerald deposit


In the Talcum Schist surrounding the Emerald bearing Muscovite and Biotite Schists of the Leckbachrinne Actinolite is a very common mineral.
Quite often the Actinolite occurs in a very appealing Emerald green colour, hence it's varietal name "Smaragdite" (Smaragd is the German word for Emerald)
The local name for the Talcum containing Actinolite pieces is "Strahlstein" ("raystone" in English) and they can be found very easily in sometimes very large specimens.

Harjo, Thats a nice little addition to the actinolite article. I have inserted it.



Edited 3 time(s). Last edit at 03/18/2009 10:06AM by Rock Currier.

Harjo, Thats a nice little addition to the actinolite article. I have inserted it. Is there another mineral you would like to start work on?

Rock Currier
Crystals not pistols.

Well, why not....
In 2005 I discovered a very good Anatase locality in the Habach Valley, Austria (it turned out to be very prolific and one of the best in the Hohe Tauern Mts) so I could write something on that.
Further I could write a piece on Emeralds from the Emerald deposit in The Habach Valley, I've got very good specimens and nice photos on that.
Also I could write something about the big Millerites from Hagen Germany (world class specimens came out of the quarry duting a couple of years, I did a Lapis article about the locality some years ago)
I'll post something about very good Fluorite specimens from Belgium (and the French Ardennes straddling the Belgian border) in the Fluorite section.
Would that be OK for now?

Cheers

Harjo