Kyanite Click here to view Best Minerals K 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? After each set of pictures there should be some descriptive text. If none appears it means that we need someone to tell us about the specimens from that locality and something about the geology of the occurrence. Kyanite Al2SiO5 Triclinic Kyanite & Quartz,17.2cm tall© Rob Lavinsky Galiléia, Doce valley, Minas Gerais Kyanite is an important metamorphic rock forming mineral and is important in determining the metamorphic conditions that the rock experienced. Kyanite is formed under high pressure, relatively low temperature ( 2+ kbars pressure and temperatures in the 350-600C range) regional metamorphic conditions where the original rock was fairly high in aluminum content (shales). The rocks will be gneisses, schists, and pegmatites and quartz veins included in these rock types. Kyanite can also survive some weathering and be found in detrital material (sands) and some sedimentary rocks. Color: Blue, white, rarely green, gray, yellow, pink, black, commonly can be zoned with central blue color and a clear outside zone. One of the minerals distinctive characteristics is the large difference in hardness which depends upon the crystallographic direction. Hardness = 5.5 parallel to [001] (c-axis), 7 parallel to [100] (a-axis). Crystals are bladed and tabular on {100}, elongated parallel to [001], to 0.5 m; typically bent or twisted. Twinning is common. From metamorphic rocks, the habit is short to long prismatic along c-axis and tabular on {100} generally less than 10 cm. In pegmatites and quartz lenses the kyanite crystal habit is long prismatic. Kyanite is polymorphous with sillimannite and andalusite. It is commonly pseudomorphed to andalusite. While kyanite is a relatively common mineral, good crystals are fairly rare. The best crystals have been found in pegmatites as well as quartz veins. Recently, Brazil has been a producer of fine specimens. Small amounts of the crystals are of facet grade, but the species is only marketable to collectors of rare stones. Kyanite Antarctica Eastern Antarctica, Enderby Land, Prince Olav Coast (Prince Ulaf Coast) Kyanite 6.5 cm wide © Pavel M. Kartashov Kyanite Australia Northern Territory, Harts Ranges (Hartz Ranges), Huckitta Well Kyanite 9cm tall © Patrick GundersenKyanite 7.5cm tall © Patrick Gundersen Kyanite crystals from the Harts Range have reached 30 cm. Kyanite Austria Styria, Ennstaler Alpen Mts, Admont, Klosterkogel Mt., Gablergraben Kyanite in schist polished slab 10cm© Franz BernhardKyanite, Polished slab 7cm wide © Franz Bernhard Kyanite Brazil Bahia Kyanite 4.1cm tall © Michael c. RoarkeKyanite 7.9cm tall© Rob Lavinsky Kyanite 26.8 cm© Rob Lavinsky Kyanite in Quartz ~20cm tall© Philip Kyanite & Quartz 16cm wide© Kyanite 6.1cm© Kyanite Brazil Goias Kyanite 2.7cm© Lavinsky blank.gif mod_embed_images_loadimage('d876f5b8c7312f8e741e41569daeba2b', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite 3.8cm© Weinrich Minerals blank.gif mod_embed_images_loadimage('f09bd6b41ba58220ce62affb42fff7f0', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite 2.4cm tall© Rob Lavinsky We need better localities for the specimens labeled just Minas Gerais, Goias and Bahia. Some of the images we show for these localities are probably not correct. Luiz, can you help us out with these? Kyanite Brazil Minas Gerais Kyanite & Quartz 11cm© Rob Lavinsky Kyanite xl 5.7cm wide, gem=1.42ct© blank.gif mod_embed_images_loadimage('886d6511f8208c6ff8c880ca30fc25a1', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); blank.gif mod_embed_images_loadimage('0767ad5eb2e5b59ec4f56410f202d217', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); blank.gif mod_embed_images_loadimage('79d1f5efbd21fe2ce19a56770c447870', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); blank.gif mod_embed_images_loadimage('306310381f7d3d866c90d696c3e592af', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite Quartz 4.9cm wide© Rob Lavinsky blank.gif mod_embed_images_loadimage('9f279bf5a96f0b0d2fa16bd74e52eb67', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); blank.gif mod_embed_images_loadimage('2434435a037f40c7c955f63c21ef61e8', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite 4.1cm wide© Rob Lavinsky Kyanite 7.5cm wide© Antonio Borrelli Kyanite 7cm wide© Marcelo O. Olsina Kyanite Brazil Minas Gerais, Doce valley, Galiléia Kyanite & Quartz 17.6cm tall© Rob Lavinsky Kyanite Brazil Minas Gerais, Jequitinhonha valley, Coronel Murta, Barra de Salinas, Barra de Salinas district blank.gif mod_embed_images_loadimage('d90c544f8842d12de7d3d585964e1924', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); blank.gif mod_embed_images_loadimage('0ff2d8cafeb7f5ccafe4e8101e172209', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite 10.5cm© blank.gif mod_embed_images_loadimage('c3adeaa041eae24ff94819eca20b833a', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite & Quartz 4.6cm tall© blank.gif mod_embed_images_loadimage('330d062efb097f76ed09453e8bdf41a3', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', 'http://www.mindat.org/images/blank.gif', 'http://www.mindat.org/forum.php?addon,77,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.mindat.org%2Fimages%2Fblank.gif', '', 165266, 600, 600, 'Loading image ...', false); Kyanite & Quartz 9.7cm© Kyanite & Quartz 19cm wide© Rob Lavinsky Kyanite Kenya Eastern Province, Makueni District, Umba Valley Region, Sultan Hamud Kyanite 18cm long© 2003 John H. Betts Kyanite 7.4 cm© Rob Lavinsky Kyanite Norway Finnmark, Hasvik, Sørøya, Båtberga Kyanite & Quartz 7cm wide© A. MichalsenKyanite in Quartz 6cm tall© A. Michalsen Kyanite Russia Urals Region, Southern Urals, Chelyabinsk Oblast', Borisovskie Sopki Kyanite in mica schist 6.4cm wide© Igor Savin Kyanite in mica schist 5.7cm wide© Igor Savin This deposit (Borisovskie Sopki) was found at the end of 19th century. Now it is developed only by mineral collectors and consists of several open pits. The largest crystals from this deposit were 20 cm long. I saw crystals with dimensions of about 15 x 3 x 1 cm. Kyanite crystals have inclusions of quartz, mica, rutile, and tourmaline. Gem material is rare. [Igor Savin 2010] Kyanite Russia Northern Region, Murmanskaja Oblast', Kola Peninsula, Keivy Mountains, Pestsovye Keivy Kyanite found in quartz lenses with crystals reaching 100cm. Also from this locality are Kyanite pseudomorphs "sausages" after chiastolite crystals 25 to 20 cm long. Unfortunately any real unreplaced andalusite absent on the locality. We need to normalize this deposit with a valid Mindat locality string. Pavel will upload an image Kyanite Switzerland Ticino (Tessin), Leventina, Central St Gotthard Massif Kyanite in mica 7.8cm tall© Rob LavinskyKyanite & Staurolite ~45cm wide © J.N. Wingard The locality for the large specimen pictured above may be in error and it is thought it is actually from Sponda Alp - Pizzo Forno, Chironico Valley, Leventina, Ticino (Tessin), Switzerland. If this is confirmed we will be moving the image. Kyanite Tanzania Arusha Region, Loliondo, Nani Kyanite twin 3.5cm wide © MAWINGU GEMS Kyanite 5cm tall© Rob Lavinsky Kyanite USA Connecticut, Fairfield Co., Redding Kyanite & Quartz ~8cm wide© Michael Otto Kyanite USA Connecticut, Litchfield Co., Litchfield Kyanite 19cm tall© Rob Lavinsky Kyanite USA North Carolina, Buncombe Co., Pisgah National Forest, Meeper Mine Kyanite & feldspar ~20cm wide© Kyanite & feldspar ~14cm wide© I'd have to say that Meeper mine probably is the best Kyanite locality in the USA bar none, some of the crystals that came out of there are on the order of 16 inches long, 3 to 4 inches wide and 1 inch thick. [Everett Harrington 2009] Kyanite USA North Carolina, Buncombe Co., Thomas Mine (Balsam Gap kyanite location; Parkway kyanite location) 1.3cm terminated Kyanite & Quartz© 2002, Keith Wood I did my MS thesis in geology on the Thomas mine, otherwise known as the Parkway or Balsam Gap sites. The main issue in my thesis was whether the Thomas occurrence was of igneous or metamorphic origin. The answer turned out to be igneous, and the reasons for this were a good deal more complicated than need be elaborated here. As part of my study I also examined the Meeper occurrence and the Swan prospect, which both also contain igneous kyanite within pegmatites. These sites are all within 1.5 miles of each other. Of these the best was the Thomas mine, named for Luther Thomas, a well-known collector in the NC mountains. Kyanite there reached lengths up to 29 inches by 3.5 inches by 1 inch - that was the single largest crystal Luther ever collected there, and I have a third of it on one ninety pound specimen in my collection. Kyanite from the Thomas mine was found in the typical white to dark blue colors, with common center zoning of the blue parts. This blue is due to ferric iron. However, many crystals, especially those in the outer zone of the pegmatite, had a rich teal coloration that XRF work showed to be related to chromium as a chromophore. This color could also be found at the Meeper mine. I have not been able to reproduce this particular color well in digital photos. This chromium coloration typically was not zoned within the crystal, whereas the ferric iron blue could be zoned in a chromium colored specimen, yielding some crystals with a solid teal coloration and a deep blue streak in the middle. Specimens with this coloration and good clarity were considered highly desirable. Another distinctive of the Thomas mine was the very high quality of the crystallization, with many less common crystal forms well represented, including several terminal forms rarely observed elsewhere. I have two well-terminated crystals in my collection, but the best terminated specimen I saw from there was a piece collected by one of the Ledford brothers in NC, a deep blue crystal 2x1x.3 inches with a complete termination. Numerous specimens of gem quality were recovered from the Thomas mine, and several gemstones were cut from this material. The best specimens were probably those collected by Luther Thomas and his son(s) in the 80s. Luther has since passed away and I assume that most of his collection went to his son Icket. The Thomas mine probably deserves to be considered the best kyanite location in North America. It bests the Meeper mine in having crystals that were less altered on the outside, often being very well exposed in the rock. Much of the Kyanite from the Meeper mine has a sericite/muscovite coating on the outside that causes the crystals to adhere to the matrix too well, resulting in cleaving of the crystals. None of these "mines" were worked commercially to anyone's knowledge, however the discovery histories and first workings are lost in obscurity. The portion of the Thomas mine Luther worked was a second pegmatite he and his son discovered down hill from an original pit of unknown origin. The original pegmatite may have been discovered during construction of the Blue Ridge Parkway, but no specimens are known to have survived. It is possible the kyanite may have been mined for use in ceramics as the waste piles of the original pit contained numerous small but very beautiful specimens that certainly would have been of mineralogical interest. It is unlikely such specimens would have been discarded had mineral collecting been the been the motive. The Meeper mine may have been discovered during mica prospecting in the area, as there are known mica-producing mines with a few miles and the entire area is in prospective rocks for mica mining. All three of the kyanite occurrences I am discussing fall within the Buncombe pegmatite district. [Keith Wood 2010] Kyanite USA North Carolina, Yancey Co., Blue Rock Asbestos Mine Kyanite & Quartz 8cm wide© 2009 M. Harrison I have just spent some hours trying to fix the mess on the Brazilian kyanite localities; I have already made the corrections on Rob Lavinski's photos and sent complaints to everybody else that have uploaded photos with wrong localities; the most common mistakes were the following: - Blue Kyanite on Quartz - there are only 2 localities in Brazil that have produced commercial quantities of high quality specimens: Barra do Salinas district, Coronel Murta, Minas Gerais (on the list of localities it is written as "Barra do Salinas district, Barra do Salinas, Coronel Murta, Jequitinhonha valley, Minas Gerais"; there is an un-necessary repetition of "Barra do Salinas"), and São José da Safira, Doce valley, Minas Gerais; I can make a distinction among them, on most cases, based on the following criteria: - the best specimens from Barra do Salinas have a deeper blue color than the best specimens from São José da Safira; tha lateral faces of the prisms tend to be pure kyanite, whilst both the main prism faces as well as the lateral faces on the crystals from São José da Safira tend to show a variable amount of intergrowth with thin white muscovite; finally, Barra do Salinas produced intensively during the 1990's until about 2004/2005, when the production started to decline sharply, and it coincides with the start of intense production from São José da Safira; unfortunately on mid to low-quality specimens it is much harder to make a distinction - there are no blue kyanites in quartz in Bahia state neither in Galileia, Araçuaí or Governador Valadares, in Minas Gerais - I have recently found out that the bicolor kyanites (green with a central blue stripe) come from Vitória da Conquista, Bahia - all black kyanites come from Ribeirão da Folha, near Capelinha, Minas Gerais; Araçuaí and Governador Valadares are wrong localities; I have not send complaint messages yet because I have to double check later today, in my office, if the locality is inside Capelinha or in Novo Cruzeiro county - there is a locality in Goias state that produced thick prismatic kyanite crystals, showing intense blue color, inside a talc-schist matrix; unfortunately I still don't know the precise locality - Brumado have produced pale blue kyanite crystals on magnesite matrix, but there were no photos of this material on the gallery; 2 photos of dark blue kyanites in quartz, listed as from there, are indeed from Barra do Salinas. [Luiz Alberto Dias Menezes, Fo. 2012-[www.mindat.org]] Click here to view Best Minerals K and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles. http://www.mindat.org/forum.php?read,77,165266,165266#msg-165266 Thu, 20 Jun 2013 05:44:36 +0000 Phorum 5.2.15a http://www.mindat.org/forum.php?read,77,165266,196129#msg-196129 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196129#msg-196129 All the specimens look just like the one I posted, sericite/feldspar mix, there are a lot of loose crystals, none that I can recall off the top of my head that were termed.


Thanks!!!!
E]]> Everett Harrington Best Minerals K Tue, 07 Sep 2010 04:21:48 +0000 http://www.mindat.org/forum.php?read,77,165266,196118#msg-196118 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196118#msg-196118
I will be able to correct most of the Brazilian kyanite localities; I am in Tucson now, finishing to sort minerals that I will be bringining to Denver, so I cannot make the corrections now; on the next few days, as soon as I can, I will send you my comments.

Luiz]]> Luiz Alberto Dias Menezes, Fo. Best Minerals K Tue, 07 Sep 2010 00:06:42 +0000 http://www.mindat.org/forum.php?read,77,165266,196091#msg-196091 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196091#msg-196091 Keith Wood Best Minerals K Mon, 06 Sep 2010 19:19:13 +0000 http://www.mindat.org/forum.php?read,77,165266,196089#msg-196089 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196089#msg-196089
Thanks. I'll think about it. I am in the midst of moving my household from one end of the state to another, so I can't promise anything soon.

Keith]]> Keith Wood Best Minerals K Mon, 06 Sep 2010 19:16:41 +0000 http://www.mindat.org/forum.php?read,77,165266,196085#msg-196085 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196085#msg-196085
This deposit (Borisovskie Sopki) was found at the end of 19th century. Now it is developed only by mineral collectors and consists of several open pits. The largest crystals from this deposit were 20 cm long. I saw crystals with dimensions of about 15 x 3 x 1 cm. Kyanite crystals have inclusions of quartz, mica, rutile, and tourmaline. Gem material is rare.

Igor]]> Igor Savin Best Minerals K Mon, 06 Sep 2010 18:21:05 +0000 http://www.mindat.org/forum.php?read,77,165266,196082#msg-196082 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196082#msg-196082 The specimen in question was in an old wooden box with about 30 others, all were very gemmy crystals and written on the box in pencil was Thomas mine, this is how I came to think this piece was from Thomas, I'll delete the location, I'm sure that Keith is spot on :)


Thanks!!

KOR
Everett]]> Everett Harrington Best Minerals K Mon, 06 Sep 2010 17:48:06 +0000 http://www.mindat.org/forum.php?read,77,165266,196080#msg-196080 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196080#msg-196080 www.mindat.org] I will upload photo of my specimen when will found it.

Note also interesting kyanite PS after chiastolite crystals [www.mindat.org] - such sausages can be 25-30 cm long. Unfortunately any real unreplaced andalusite absent on the locality.]]> Pavel Kartashov Best Minerals K Mon, 06 Sep 2010 17:41:40 +0000 http://www.mindat.org/forum.php?read,77,165266,196062#msg-196062 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196062#msg-196062 I like them and have added them to the Best Minerals article. Can you tell me something of the locality? Open pit? Still collectible material there? How big do the crystals get? Look like they may produce some gem material?]]> Rock Currier Best Minerals K Mon, 06 Sep 2010 13:01:38 +0000 http://www.mindat.org/forum.php?read,77,165266,196057#msg-196057 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196057#msg-196057 You are right about the general localities for the images of the Brazilian kyanites we now show. We hope to soon correct this because these are really too general to stay for long in the best minerals Kyanite article. They are there because the Kyanite from various Brazilian localities is so common in collections around the world that we put them there till we can get more accurate locality information which we hope to soon now have in hand.]]> Rock Currier Best Minerals K Mon, 06 Sep 2010 12:30:51 +0000 http://www.mindat.org/forum.php?read,77,165266,196054#msg-196054 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196054#msg-196054
[www.mindat.org]

[www.mindat.org]]]> Igor Savin Best Minerals K Mon, 06 Sep 2010 11:28:58 +0000 http://www.mindat.org/forum.php?read,77,165266,196050#msg-196050 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196050#msg-196050 What you wrote is very interesting and much if not most or all of it should be incorporated into the article. Would you consider rewriting the article for us? I think you know much more about Kyanite than most. I will go through the article and clean it up a little, which will mostly consist of tweaking and arranging the photographs in a format that is a bit closer to our current standard. I am sure that David would be glad for your input. What do you say?]]> Rock Currier Best Minerals K Mon, 06 Sep 2010 08:41:06 +0000 http://www.mindat.org/forum.php?read,77,165266,196043#msg-196043 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196043#msg-196043
Bill]]> William W Besse Best Minerals K Mon, 06 Sep 2010 04:04:04 +0000 http://www.mindat.org/forum.php?read,77,165266,196032#msg-196032 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,196032#msg-196032
As part of my study I also examined the Meeper occurrence and the Swan prospect, which both also contain igneous kyanite within pegmatites. These sites are all within 1.5 miles of each other. Of these the best was the Thomas mine, named for Luther Thomas, a well-known collector in the NC mountains. Kyanite there reached lengths up to 29 inches by 3.5 inches by 1 inch - that was the single largest crystal Luther ever collected there, and I have a third of it on one ninety pound specimen in my collection. Kyanite from the Thomas mine was found in the typical white to dark blue colors, with common center zoning of the blue parts. This blue is due to ferric iron. However, many crystals, especially those in the outer zone of the pegmatite, had a rich teal coloration that XRF work showed to be related to chromium as a chromophore. This color could also be found at the Meeper mine. I have not been able to reproduce this particular color well in digital photos. This chromium coloration typically was not zoned within the crystal, whereas the ferric iron blue could be zoned in a chromium colored specimen, yielding some crystals with a solid teal coloration and a deep blue streak in the middle. Specimens with this coloration and good clarity were considered highly desirable.

Another distinctive of the Thomas mine was the very high quality of the crystallization, with many less common crystal forms well represented, including several terminal forms rarely observed elsewhere. I have two well-terminated crystals in my collection, but the best terminated specimen I saw from there was a piece collected by one of the Ledford brothers in NC, a deep blue crystal 2x1x.3 inches with a complete termination. Numerous specimens of gem quality were recovered from the Thomas mine, and several gemstones were cut from this material.

The best specimens were probably those collected by Luther Thomas and his son(s) in the 80s. Luther has since passed away and I assume that most of his collection went to his son Icket.

The Thomas mine probably deserves to be considered the best kyanite location in North America. It bests the Meeper mine in having crystals that were less altered on the outside, often being very well exposed in the rock. Much of the Kyanite from the Meeper mine has a sericite/muscovite coating on the outside that causes the crystals to adhere to the matrix too well, resulting in cleaving of the crystals.

None of these "mines" were worked commercially to anyone's knowledge, however the discovery histories and first workings are lost in obscurity. The portion of the Thomas mine Luther worked was a second pegmatite he and his son discovered down hill from an original pit of unknown origin. The original pegmatite may have been discovered during construction of the Blue Ridge Parkway, but no specimens are known to have survived. It is possible the kyanite may have been mined for use in ceramics as the waste piles of the original pit contained numerous small but very beautiful specimens that certainly would have been of mineralogical interest. It is unlikely such specimens would have been discarded had mineral collecting been the been the motive. The Meeper mine may have been discovered during mica prospecting in the area, as there are known mica-producing mines with a few miles and the entire area is in prospective rocks for mica mining. All three of the kyanite occurrences I am discussing fall within the Buncombe pegmatite district.

By the way, Everett, I'm sorry to say, but it is extremely unlikely that your "Thomas Mine" specimen is actually from the Thomas mine. I say this for several reasons. The crystallization quality is obviously below that of your (rightly attributed) Meeper mine specimen. Also the sericite/muscovite coatings on the kyanite crystals is quite unlike anything observed at the Thomas mine, which as I mentioned has better preservation of the crystals than even the Meeper mine. From all the kyanite sites I visited in the NC mountains your "Thomas" specimen seems most likely to have originated on or near Celo Knob. It has been common practice for collectors in the region to attribute specimens to the Thomas mine as an attempt to increase the value of the specimens, but the Thomas pieces are too distinctive to be confused with other pieces. I'm sorry to have to mention this.

Rock, the typical Brazilian kyanite does not come from pegmatites in the igneous sense of that word, although it certainly comes from pegmatites if grain size is the only consideration. Genetically these are related to metamorphic processes, which in Brazil's case provided conditions far more favorable than similar settings in North America. However, most kyanite occurrences are of metamorphic origin, and to my knowledge the ones I worked on are the only ones where igneous conditions of formation were rigorously demonstrated. However, from my expierience with kyanite, I think there is reason to believe that some of the less typical kyanite specimens from Brazil may also be of igneous origin, specifically the ones with green/blue coloration posted by Rob Lavinsky and Michael Roarke, above. These are interesting as kyanite specimens because unlike the huge number of kyanite-in-quartz specimens from Brazil, these never appeared on the market with matrix. Indeed they nearly always look a bit worn as though recovered from colluvial or alluvial occurrences. The crystallization of these specimens is exceptionally good, truly the best in Brazil, and definitely on par with that observed at the Thomas mine. I have long suspected these weathered out of an igneous source similar to that at the Thomas mine, and were recovered from soil downslope. These are the crystals I am referring to:

© Rob Lavinsky
© Lavinsky
© Michael c. Roarke
©
© Rob Lavinsky
© Rob Lavinsky


Another location possibly producing igneous kyanite is the exceptional material from Kenya illustrated above with this picture:
© 2003 John H. Betts

This material emerged on the market decades ago and is seldom seen these days. The coloration and crystallization of these specimens is very similar to material from the Thomas mine, but again no matrix specimens exist to my (in this case quite limited) knowledge.

Rock, I would suggest this specimen be added to this article. It is one of the few perfectly terminated matrix specimens from the Thomas mine, an exceptional North American kyanite as far as crystallization is concerned.
© 2002, Keith Wood
]]> Keith Wood Best Minerals K Sun, 05 Sep 2010 22:56:48 +0000 http://www.mindat.org/forum.php?read,77,165266,172010#msg-172010 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,172010#msg-172010
I realize that my image is not of the highest standard. I am not really set up for professional quality photos. The Brazilian state of Bahia is the size of Utah, also a big place. If a precise location is required for inclusion, it would be useful to put it in the report.

Dennis]]> Dennis Tryon Best Minerals K Thu, 11 Feb 2010 23:49:43 +0000 http://www.mindat.org/forum.php?read,77,165266,171989#msg-171989 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171989#msg-171989 Rock Currier Best Minerals K Thu, 11 Feb 2010 20:19:43 +0000 http://www.mindat.org/forum.php?read,77,165266,171524#msg-171524 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171524#msg-171524
Seems like Karur, India is about as descriptive as Bahia, Brazil. Am I missing something?

Dennis]]> Dennis Tryon Best Minerals K Sun, 07 Feb 2010 20:31:37 +0000 http://www.mindat.org/forum.php?read,77,165266,171517#msg-171517 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171517#msg-171517 Thanks for the email and the image, but without some more information about the place we would not want to put this in best minerals.]]> Rock Currier Best Minerals K Sun, 07 Feb 2010 18:48:37 +0000 http://www.mindat.org/forum.php?read,77,165266,171413#msg-171413 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171413#msg-171413
Dennis]]> Dennis Tryon Best Minerals K Sat, 06 Feb 2010 22:57:40 +0000 http://www.mindat.org/forum.php?read,77,165266,171381#msg-171381 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171381#msg-171381 David Bernstein Best Minerals K Sat, 06 Feb 2010 20:27:29 +0000 http://www.mindat.org/forum.php?read,77,165266,171366#msg-171366 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171366#msg-171366 I think it might be useful to upload an image or two of the locality to mindat. It would be interesting to know what the locality looked like. When was kyanite found there? Was it ever a commercial mine? Can specimens still be collected there? How many specimens have been collected. Your note on how big the crystals get was useful. Was any gem material produced? Where is the best specimen located. All the various kinds of things that collectors might want to know. Any terminated crystals? Anything that definitely sets them apart from the Brazilian material? Are not those specimens also from pegmatites?]]> Rock Currier Best Minerals K Sat, 06 Feb 2010 17:59:57 +0000 http://www.mindat.org/forum.php?read,77,165266,171188#msg-171188 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171188#msg-171188
According to Gramaccioli "Die Mineralien der Alpen" the paragenesis is: andalousite, sillimanite, staurolite, kyanite, paragonite (TL!), muskovite. From personal finds I may add black tourmaline in biotite schist, some epidote, albite variety pericline. The book 'Die Mineralien der Schweiz" by Max Weibel e.a. says on p 176 (in translation): "The best specimens are found in light-coloured, mica-rich masses, often on the edge of the many quartzlenses".

And in Europe, the name 'rhätizite" (derived from the Rhätische Alpen) is/was used for gray, rock forming kyanite.]]> Erik Vercammen Best Minerals K Thu, 04 Feb 2010 21:01:47 +0000 http://www.mindat.org/forum.php?read,77,165266,171148#msg-171148 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171148#msg-171148 I need to know which one you'd prefer? I can give info on all, I'd have to say that Meeper mine prob is the best kyanite in the USA bar none, some of the crystals that came out of there are on the order of 16 inches long, 3 to 4 inches wide and 1 inch thick. One of the only pegmatic kyanite locations in the world! So Should we go with that photo?

Thanks
KOR
E]]> Everett Harrington Best Minerals K Thu, 04 Feb 2010 15:27:42 +0000 http://www.mindat.org/forum.php?read,77,165266,171103#msg-171103 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,171103#msg-171103 We can probably find a place for one of your specimens in the kyanite article. What can you tell us about the locality and the specimens it produces.]]> Rock Currier Best Minerals K Thu, 04 Feb 2010 06:57:59 +0000 http://www.mindat.org/forum.php?read,77,165266,170728#msg-170728 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,170728#msg-170728 I've added some of my US kyanite specimens to the mindat database, here are links to a few that might be used here?

[www.mindat.org]

[www.mindat.org]

[www.mindat.org]


Enjoy!!
E]]> Everett Harrington Best Minerals K Mon, 01 Feb 2010 04:14:13 +0000 http://www.mindat.org/forum.php?read,77,165266,165563#msg-165563 Re: Kyanite http://www.mindat.org/forum.php?read,77,165266,165563#msg-165563 Excellent work.]]> Rock Currier Best Minerals K Wed, 30 Dec 2009 10:01:00 +0000 http://www.mindat.org/forum.php?read,77,165266,165266#msg-165266 Kyanite http://www.mindat.org/forum.php?read,77,165266,165266#msg-165266 Best Minerals K 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? After each set of pictures there should be some descriptive text. If none appears it means that we need someone to tell us about the specimens from that locality and something about the geology of the occurrence.

Kyanite
Al2SiO5 Triclinic

Kyanite & Quartz,17.2cm tall© Rob Lavinsky

Galiléia, Doce valley, Minas Gerais

Kyanite is an important metamorphic rock forming mineral and is important in determining the metamorphic conditions that the rock experienced. Kyanite is formed under high pressure, relatively low temperature ( 2+ kbars pressure and temperatures in the 350-600C range) regional metamorphic conditions where the original rock was fairly high in aluminum content (shales). The rocks will be gneisses, schists, and pegmatites and quartz veins included in these rock types. Kyanite can also survive some weathering and be found in detrital material (sands) and some sedimentary rocks.

Color: Blue, white, rarely green, gray, yellow, pink, black, commonly can be zoned with central blue color and a clear outside zone.

One of the minerals distinctive characteristics is the large difference in hardness which depends upon the crystallographic direction. Hardness = 5.5 parallel to [001] (c-axis), 7 parallel to [100] (a-axis).

Crystals are bladed and tabular on {100}, elongated parallel to [001], to 0.5 m; typically bent or twisted. Twinning is common. From metamorphic rocks, the habit is short to long prismatic along c-axis and tabular on {100} generally less than 10 cm. In pegmatites and quartz lenses the kyanite crystal habit is long prismatic.

Kyanite is polymorphous with sillimannite and andalusite. It is commonly pseudomorphed to andalusite.

While kyanite is a relatively common mineral, good crystals are fairly rare. The best crystals have been found in pegmatites as well as quartz veins. Recently, Brazil has been a producer of fine specimens. Small amounts of the crystals are of facet grade, but the species is only marketable to collectors of rare stones.


Kyanite
Antarctica
Eastern Antarctica, Enderby Land, Prince Olav Coast (Prince Ulaf Coast)

Kyanite 6.5 cm wide © Pavel M. Kartashov



Kyanite
Australia
Northern Territory, Harts Ranges (Hartz Ranges), Huckitta Well

Kyanite 9cm tall © Patrick Gundersen
Kyanite 7.5cm tall © Patrick Gundersen

Kyanite crystals from the Harts Range have reached 30 cm.


Kyanite
Austria
Styria, Ennstaler Alpen Mts, Admont, Klosterkogel Mt., Gablergraben

Kyanite in schist polished slab 10cm© Franz Bernhard
Kyanite, Polished slab 7cm wide © Franz Bernhard


Kyanite
Brazil
Bahia

Kyanite 4.1cm tall © Michael c. Roarke
Kyanite 7.9cm tall© Rob Lavinsky


Kyanite 26.8 cm© Rob Lavinsky
Kyanite in Quartz ~20cm tall© Philip


Kyanite & Quartz 16cm wide©
Kyanite 6.1cm©


Kyanite
Brazil
Goias

Kyanite 2.7cm© Lavinsky
Kyanite 3.8cm© Weinrich Minerals
Kyanite 2.4cm tall© Rob Lavinsky


We need better localities for the specimens labeled just Minas Gerais, Goias and Bahia. Some of the images we show for these localities are probably not correct. Luiz, can you help us out with these?



Kyanite
Brazil
Minas Gerais

Kyanite & Quartz 11cm© Rob Lavinsky
Kyanite xl 5.7cm wide, gem=1.42ct©


Kyanite Quartz 4.9cm wide© Rob Lavinsky
Kyanite 4.1cm wide© Rob Lavinsky



Kyanite 7.5cm wide© Antonio Borrelli
Kyanite 7cm wide© Marcelo O. Olsina


Kyanite
Brazil
Minas Gerais, Doce valley, Galiléia

Kyanite & Quartz 17.6cm tall© Rob Lavinsky



Kyanite
Brazil
Minas Gerais, Jequitinhonha valley, Coronel Murta, Barra de Salinas, Barra de Salinas district

Kyanite 10.5cm©
Kyanite & Quartz 4.6cm tall©
Kyanite & Quartz 9.7cm©



Kyanite & Quartz 19cm wide© Rob Lavinsky



Kyanite
Kenya
Eastern Province, Makueni District, Umba Valley Region, Sultan Hamud

Kyanite 18cm long© 2003 John H. Betts
Kyanite 7.4 cm© Rob Lavinsky


Kyanite
Norway
Finnmark, Hasvik, Sørøya, Båtberga

Kyanite & Quartz 7cm wide© A. Michalsen
Kyanite in Quartz 6cm tall© A. Michalsen



Kyanite
Russia
Urals Region, Southern Urals, Chelyabinsk Oblast', Borisovskie Sopki

Kyanite in mica schist 6.4cm wide© Igor Savin
Kyanite in mica schist 5.7cm wide© Igor Savin

This deposit (Borisovskie Sopki) was found at the end of 19th century. Now it is developed only by mineral collectors and consists of several open pits. The largest crystals from this deposit were 20 cm long. I saw crystals with dimensions of about 15 x 3 x 1 cm. Kyanite crystals have inclusions of quartz, mica, rutile, and tourmaline. Gem material is rare.
[Igor Savin 2010]


Kyanite
Russia
Northern Region, Murmanskaja Oblast', Kola Peninsula, Keivy Mountains, Pestsovye Keivy

Kyanite found in quartz lenses with crystals reaching 100cm. Also from this locality are Kyanite pseudomorphs "sausages" after chiastolite crystals 25 to 20 cm long. Unfortunately any real unreplaced andalusite absent on the locality.

We need to normalize this deposit with a valid Mindat locality string. Pavel will upload an image


Kyanite
Switzerland
Ticino (Tessin), Leventina, Central St Gotthard Massif

Kyanite in mica 7.8cm tall© Rob Lavinsky
Kyanite & Staurolite ~45cm wide © J.N. Wingard

The locality for the large specimen pictured above may be in error and it is thought it is actually from Sponda Alp - Pizzo Forno, Chironico Valley, Leventina, Ticino (Tessin), Switzerland. If this is confirmed we will be moving the image.


Kyanite
Tanzania
Arusha Region, Loliondo, Nani

Kyanite twin 3.5cm wide © MAWINGU GEMS
Kyanite 5cm tall© Rob Lavinsky



Kyanite
USA
Connecticut, Fairfield Co., Redding

Kyanite & Quartz ~8cm wide© Michael Otto


Kyanite
USA
Connecticut, Litchfield Co., Litchfield

Kyanite 19cm tall© Rob Lavinsky


Kyanite
USA
North Carolina, Buncombe Co., Pisgah National Forest, Meeper Mine

Kyanite & feldspar ~20cm wide©
Kyanite & feldspar ~14cm wide©

I'd have to say that Meeper mine probably is the best Kyanite locality in the USA bar none, some of the crystals that came out of there are on the order of 16 inches long, 3 to 4 inches wide and 1 inch thick.
[Everett Harrington 2009]


Kyanite
USA
North Carolina, Buncombe Co., Thomas Mine (Balsam Gap kyanite location; Parkway kyanite location)

1.3cm terminated Kyanite & Quartz© 2002, Keith Wood


I did my MS thesis in geology on the Thomas mine, otherwise known as the Parkway or Balsam Gap sites. The main issue in my thesis was whether the Thomas occurrence was of igneous or metamorphic origin. The answer turned out to be igneous, and the reasons for this were a good deal more complicated than need be elaborated here.

As part of my study I also examined the Meeper occurrence and the Swan prospect, which both also contain igneous kyanite within pegmatites. These sites are all within 1.5 miles of each other. Of these the best was the Thomas mine, named for Luther Thomas, a well-known collector in the NC mountains. Kyanite there reached lengths up to 29 inches by 3.5 inches by 1 inch - that was the single largest crystal Luther ever collected there, and I have a third of it on one ninety pound specimen in my collection. Kyanite from the Thomas mine was found in the typical white to dark blue colors, with common center zoning of the blue parts. This blue is due to ferric iron. However, many crystals, especially those in the outer zone of the pegmatite, had a rich teal coloration that XRF work showed to be related to chromium as a chromophore. This color could also be found at the Meeper mine. I have not been able to reproduce this particular color well in digital photos. This chromium coloration typically was not zoned within the crystal, whereas the ferric iron blue could be zoned in a chromium colored specimen, yielding some crystals with a solid teal coloration and a deep blue streak in the middle. Specimens with this coloration and good clarity were considered highly desirable.

Another distinctive of the Thomas mine was the very high quality of the crystallization, with many less common crystal forms well represented, including several terminal forms rarely observed elsewhere. I have two well-terminated crystals in my collection, but the best terminated specimen I saw from there was a piece collected by one of the Ledford brothers in NC, a deep blue crystal 2x1x.3 inches with a complete termination. Numerous specimens of gem quality were recovered from the Thomas mine, and several gemstones were cut from this material. The best specimens were probably those collected by Luther Thomas and his son(s) in the 80s. Luther has since passed away and I assume that most of his collection went to his son Icket.

The Thomas mine probably deserves to be considered the best kyanite location in North America. It bests the Meeper mine in having crystals that were less altered on the outside, often being very well exposed in the rock. Much of the Kyanite from the Meeper mine has a sericite/muscovite coating on the outside that causes the crystals to adhere to the matrix too well, resulting in cleaving of the crystals.

None of these "mines" were worked commercially to anyone's knowledge, however the discovery histories and first workings are lost in obscurity. The portion of the Thomas mine Luther worked was a second pegmatite he and his son discovered down hill from an original pit of unknown origin. The original pegmatite may have been discovered during construction of the Blue Ridge Parkway, but no specimens are known to have survived. It is possible the kyanite may have been mined for use in ceramics as the waste piles of the original pit contained numerous small but very beautiful specimens that certainly would have been of mineralogical interest. It is unlikely such specimens would have been discarded had mineral collecting been the been the motive. The Meeper mine may have been discovered during mica prospecting in the area, as there are known mica-producing mines with a few miles and the entire area is in prospective rocks for mica mining. All three of the kyanite occurrences I am discussing fall within the Buncombe pegmatite district.
[Keith Wood 2010]

Kyanite
USA
North Carolina, Yancey Co., Blue Rock Asbestos Mine

Kyanite & Quartz 8cm wide© 2009 M. Harrison


I have just spent some hours trying to fix the mess on the Brazilian kyanite localities; I have already made the corrections on Rob Lavinski's photos and sent complaints to everybody else that have uploaded photos with wrong localities; the most common mistakes were the following:

- Blue Kyanite on Quartz - there are only 2 localities in Brazil that have produced commercial quantities of high quality specimens: Barra do Salinas district, Coronel Murta, Minas Gerais (on the list of localities it is written as "Barra do Salinas district, Barra do Salinas, Coronel Murta, Jequitinhonha valley, Minas Gerais"; there is an un-necessary repetition of "Barra do Salinas"), and São José da Safira, Doce valley, Minas Gerais; I can make a distinction among them, on most cases, based on the following criteria:
- the best specimens from Barra do Salinas have a deeper blue color than the best specimens from São José da Safira; tha lateral faces of the prisms tend to be pure kyanite, whilst both the main prism faces as well as the lateral faces on the crystals from São José da Safira tend to show a variable amount of intergrowth with thin white muscovite; finally, Barra do Salinas produced intensively during the 1990's until about 2004/2005, when the production started to decline sharply, and it coincides with the start of intense production from São José da Safira; unfortunately on mid to low-quality specimens it is much harder to make a distinction
- there are no blue kyanites in quartz in Bahia state neither in Galileia, Araçuaí or Governador Valadares, in Minas Gerais
- I have recently found out that the bicolor kyanites (green with a central blue stripe) come from Vitória da Conquista, Bahia
- all black kyanites come from Ribeirão da Folha, near Capelinha, Minas Gerais; Araçuaí and Governador Valadares are wrong localities; I have not send complaint messages yet because I have to double check later today, in my office, if the locality is inside Capelinha or in Novo Cruzeiro county
- there is a locality in Goias state that produced thick prismatic kyanite crystals, showing intense blue color, inside a talc-schist matrix; unfortunately I still don't know the precise locality
- Brumado have produced pale blue kyanite crystals on magnesite matrix, but there were no photos of this material on the gallery; 2 photos of dark blue kyanites in quartz, listed as from there, are indeed from Barra do Salinas.
[Luiz Alberto Dias Menezes, Fo. 2012-[www.mindat.org]]



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]]> David Von Bargen Best Minerals K Mon, 28 Dec 2009 20:17:30 +0000