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My Mineral Collection, Pyrope and Miscellaneous Garnets Page

This is my pyrope and miscellaneous garnet collection. Pure pyropes are unknown (in nature) - there's always some almandine and spessartine present - pure pyropes would be colorless. I have so few pyropes that I've decided to combine them with the lesser known garnets.
Miscellaneous Garnet Info
Garnet Varieties
The six common varieties form two composition-related groups (solely for classification purposes):
  • aluminum garnets, pyralspites (pyrope, almandine, spessartine) - the vast majority of gemstone garnets
  • calcium garnets, ugrandites (uvarovite, grossular, andradite) - widest color range
in which there's a complete solid solution series between the following species:
  1. pyrope : almandine : spessartine
  2. andradite : grossular : uvarovite (may be only partial series)
and only partial series between the two groups. Garnets come in every color except blue - though some of the color-change ones do pass through a blue phase under certain lighting conditions.

The less common varieties are:

See MinDat's page for a complete listing of the Garnet Group.

Generically, garnets have the formula: A3B2(SiO4)3 where A can be Ca, Fe (ferrous), Mg, Mn (manganous) and B can be Al, Fe (ferric), Mn (manganic), Cr, Ti, V, Zr with iron and aluminum occasionally replacing some of the silicon. The number of combinations is reflected in their diverse color range. To include the synthetic garnets, the formula can be rewritten as A3B2(CO4)3, or even A3B5O12 since in synthetic garnets, B and C are usually the same element. Here, A can also include bismuth, gadolinium, and yttrium and B can include gallium and vanadium.

Color-change garnets
Some pyropes and spessartines are color-change garnets (thanks to Joel Arem's Color Encyclopedia of Gemstones and others):

LocalityIncandescent / Daylight, Fluorescent (transmitted / reflected)
 
pyrope-almandite (rhodolite)
North Pare Mountains, Tanzaniapurplish red / blue
pyrope-spessartine (pyrospessartite)
Bekily, Madagascar (1999)plum red / bluish-green
Norwegianwine red / violet
Wellawaya, Sri Lanka (1996)purplish red / dark bluish green
Tunduru, Tanzaniaintense red / greenish gold
Tanzaniatan / light green
Tanzaniapurplish red / brownish green
Umba Valley, East Africamagenta / greenish-blue
Voi, Kenyapinkish orange / medium brownish yellow
spessartine-grossular-almandine
East Africareddish orange to red / greenish yellow-brown / purplish red
spessartine-grossular-pyrope
East Africalight red to purplish red / light bluish green / purple
alexandrite-type spessartine
Unknownviolet-red / blue-green
andradite
Russiaolive-green / orange [photo courtesy of Thai Gems]

There's also some mixed garnets (two or more species on one matrix) and some combination garnets. Most garnets are not purely one species but the combination ones here are known to be "midway". Malaya (Malaia) garnets are a mix of pyrope, spessartine, and grossular (significant vanadium impurities create the color-change variety), rhodolites (and Mozambiques - red w/ orange flashes; the mine is now closed) are a combination of pyrope and almandine, and Mali garnets (1994) are a rare mixture of andradite and grossular (grandite). Grape (violet to purplish-red) garnets are almandine-spessartines from the Orissa district of northwestern India. Some garnets can be combinations of more than three species - in 1994, in Slovakia, there's an unusual vanadium-chromium garnet that's part goldmanite, uvarovite, grossular, and yamatoite.

Synthetic and homocreate garnets
I also have a few lab-produced (faceted) garnets - these garnets can be either homocreate (same composition as natural garnets) or synthetic, that is, not having a natural counterpart. Homocreated created garnets are relatively difficult to fabricate and since, in general, natural garnets are relartively cheap, there's not much incentive to manufacture them. "Synthetic garnets" (especially with the same garnet name as the natural ones) for jewelry are almost always colored synthetic spinels. Most of the true synthesized garnets are doped YAGs - yttrium aluminum garnets. I have a cesium-doped (yellow) and a chromium-doped (green) YAG. Both are highly fluorescent - the green one has a green-red color change.

Synthetic garnets have other uses than gemstones - yttrium-iron garnets (YIG) are magnetic and find many uses as sensors, actuators, and microwave substrates.

Finally, there's a few unidentified garnets here.

New garnets!
From the abstract of A natural scandian garnet. in American Mineralogist, Volume 90, 1688 - 1692, 2005.

Garnet from an aposkarn achtarandite-bearing rodingite-like rock in Sakha-Yakutia, Russia, has a Sc content close to 6 wt% Sc2O3 . . . Investigation of the composition of many of the scandian garnets reveals the existence of a solid-solution between kimzeyite-schorlomite Ca3(Zr,Ti)2(Al,Fe)2SiO12 and the scandium analog of andradite Ca3Sc2Si3O12. This is the first report of a natural scandian garnet.

From the abstract at Neues Jahrbuch fur Mineralogie-Monatshefte 1999, Vol , Iss 3, pp 123 - 134:

"Schaferite, a new member of the garnet group, has been discovered in a fragment of a silicate-rich xenolith from the Bellberg volcano near Mayen, Eifel, Germany. . . . Schaferite has an orange-red colour and a vitreous lustre, the streak is yellow. . . . the simplified formula as derived from chemical analyses and crystal-structure investigation is NaCa2Mg2(VO4)3."

The "vanadate" allies it with the goldmanite-yamatoite subgroup.

Garnets on Other Pages
See my other garnet pages; almandines, andradites, grossulars, spessartines, and uvarovites

Also, see my other nesosilicates

Specimens on This Page
(links take you to either the first or only specimen)

10 Rows

Almandine
Spessartine

A bunch of deep red almandine-spessartines in massive garnet matrix from Afghanistan - most of them have internal fractures but they're still very clean and colorful!

Andradite and
Grossular

Mixed andradite and grossular garnets (even within single crystals) from old Spanish gold mines at San Pedro Mountain, Santa Fe County, New Mexico.This specimen was collected at least 50 years ago!

Thanks to Mel Stairs's auction on eBay for the specimen!

Calderite

This miniature of rare light-red calderite in a (highly) magnetic manganese-iron oxide matrix is from the Champion Iron Mine, Champion, Marquette County, Michigan. Calderite can be thought of as a grossular with added manganese and iron.

Thanks to Thomas Bee's auction on eBay for the specimen!

Row 2

Garnets

Probably almandines in a schist that's partly blue glaucophane from Camp Meeker, Sonoma County, California.

Thanks to Tom Lettier and Ken Balthazor's (The California Crystal Connection) auction on eBay for the specimen!

Garnet

A big garnet (probably andradite) with attached schorl and quartz.

Thanks to Mary Sue Bailey's auction on eBay for the specimen and images!

Garnets

A waterworn rock full of garnets (probably rhodolite) from Rhode Island.

Thanks to Mike Yaseen's auction on eBay for the specimen!

Row 3

Garnets

This is an odd micromount from the Sa Duchessa Mine, Oridda, Domusnovas, Iglesiente district, Cagliari Province, Sardinia, Italy - an unknown variety of garnet with copper minerals!

Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!

Garnets

A couple of interesting garnets from South Africa - note the complex faces and growth.

Thanks to Mike Keim at Marin Minerals for the specimen and the image!

Garnets

A pair of garnet-laden rocks - location unknown, just a good example of garnets in matrix.

Thanks to Russ Morris's auction on eBay for the specimen and images!

Row 4

Goldmanite

Goldmanite is also fairly and occurs as pale green druses (mostly north of the red arrow) on this thumbnail from Ehime-ken, Shikoku, Japan - the only garnet from Japan that I have!

Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!

Goldmanite

An excellent micro of dozens of tiny goldmanites on matrix from the Gambatesa Mine in the Graveglia Valley, Genova Province, Liguria, Italy.

Thanks to Paolo Bracci's auction on eBay for the specimen and the image!

Kimzeyite

Kimzeyite's a very rare zirconium / titanium garnet (often referred to as just "zirconium garnet" since the titanium content is only around 4%) in the ugrandite group. This one's from Perovskite Hill, Magnet Cove, Hot Spring County, Arkansas. It's named after the Kimzey family, also of Magnet Cove.

Thanks to Anne & Charles Steuart's auction on eBay for the specimen!

Row 5

Kimzeyite

A nice miniature of three dark-brown kimzeyites in carbonatite with quartz from the type locality of the Kimsey Calcite Quarry in Magnet Cove, Hot Spring County, Arkansas.

Thanks to Leland Goodwin's auction on eBay for the specimen and the images!

Kimzeyite

A 1mm modified dodecahedron kimzeyite, also from the type locality.

Thanks to Chris Stefano's Christopher J. Stefano Fine Minerals auction on eBay for the specimen and the image!

Mali Garnet

Mali garnets (grandites) are from a 1994 find in the west African Republic of Mali - they're a rare mixture of andradite and grossular and can vary in color from chartreuse to deep brown.

Thanks to David Selem's auction on eBay for the specimen and image!

Row 6

Mali Garnet

Here's a Mali with a more typical color - too bad it's it only a centimeter across!

Mali Garnet

Here is a big Mali garnet - over two inches across and just under a pound! It has some translucent areas, as shown by the sidelit closeup (larger image, bottom left).

Thanks to Mary Sue Bailey's auction on eBay for the specimen and the images!

Manganoan
Almandine

This beautiful cluster of garnets from Groves Quarry, Auburn, Androscoggin County, Maine, has a composition between almandine and spessartine (about a third of the iron is replaced by managanese).

Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen and analysis!

Row 7

Mixed Garnets

This is an odd specimen from the Coyote Front Range near Bishop, California. It's got both andradite and grossular garnets on a (very) friable matrix with light green diopside and green needles of epidote.

Thanks to Chris Korpi at Pangaea Minerals for the specimen!

Pyrope

Pyrope, I think, from Gilgit, Pakistan - the color's right.

Thanks to Jan Garland's (Fine Rocks) auction on eBay for the specimen!

Pyrope

This pyrope in a quartz matrix is from the Limpopo River in South Africa.

Thanks to Dan Kepler's (minertown) auction on eBay for the specimen!

Row 8

Eclogitic Pyrope

Often pyropes appear in a pyroxene matrix, along with other, rarer minerals. These associations are called eclogites (from the Greek word for chosen or selected, because of their beauty) - this one with red pyropes (see the extreme closeup, larger picture) in black pyroxene is from San Benito County, California.

Thanks to Wayne Bloechl's (GeoJoe's) auction on eBay for the specimen!

Pyrope

These appear to be pyropes from Pakistan.

Thanks to Frank Elsen's auction on eBay for the specimen!

Pyrope

A 5mm pyrope on mica from Governador Valadares, Doce valley, Minas Gerais, Brazil.

Thanks to S Khalsa's auction on eBay for the specimen and the images!

Row 9

Pyrope
Almandine

A big beautiful bright pyrope-almandine from Brazill.

Thanks to Natalia Monsievich's auction on eBay for the specimen!

Green Pyrope

The chemical composition of pyrope precludes any allochromatism but these mint-green pyropes (this specimen's a miniature) from the 2010 find at Gulbahar, Afganistan were still a surprise.

Thanks to SoCal Nevada's auction on eBay for the specimen and images!

Schorlomite

Schorlomite's a rare titanium-rich member of the ugrandite garnet subfamily. There's also aegirine, cancrinite, and nepheline in this specimen from the Turii alkaline Massif, Turii Cape, Kola Peninsula, Russia.

Thanks to Tim Jokela, Jr. at Element 51 for the specimen!

Row 10

Schorlomite

Two miniatures (see larger image) of massive schorlomite from the Branch Creek, Magnet Cove, Hot Spring County, Arkansas. The Magnet Cove area is the type locality for schorlomite.

Thanks to Wayne Rudolph's auction on eBay for the specimen!

Spessartine
Almandine

A tiny (6 mm) spessartine-almandine hybrid from the Antelope Ridge, near Topaz Mountain, Thomas Range, Juab County, Utah. The surface has also begun to alter.

Thanks to Greg Holland at the Stone Haven Mineral Shoppe for the specimen!

Spessartine
Andradite

This is a hybrid of spessartine and andradite from the Aquarius Mountains, Mojave County, Arizona.

Thanks to Terri Zahorniak's auction on eBay for the specimen!

maintained by: Alan Guisewite

Last Update 6 Mar 2011