Marin Mineral
Gemstones!
April 22, 2011  ·  25 specimens

AF109 - Tanzanite  sold

Merelani Hills, Tanzania
Thumbnail - 2.6 x 0.7 x 0.6 cm



(click on an image to enlarge)

Tanzanite Tanzanite

Glassy and lustrous gem Tanzanite crystal that is very gemmy from top to bottom. Complete and undamaged, highly gemmy, overall excellent quality. Natural, unheated gem Tanzanite crystal. Illustrated in the Sept.-Oct. 2009 issue of the Mineralogical Record (Figure 84, page 386). 13.2 carats in weight, 2.6 x 0.7 x 0.6 cm.


AF133 - Tanzanite  sold

Merelani Hills, Tanzania
Thumbnail - 1.8 x 0.8 x 0.5 cm



(click on an image to enlarge)

Tanzanite Tanzanite Tanzanite

Glassy and lustrous gem Tanzanite crystal that is very gemmy from top to bottom. Though small, it was selected from gem rough and has great overall form, color, and transparency. Natural, unheated gem Tanzanite crystal, 1.8 x 0.8 x 0.5 cm.

AF134 - Tanzanite  sold

Merelani Hills, Tanzania
Thumbnail - 1.7 x 0.7 x 0.5 cm



(click on an image to enlarge)

Tanzanite Tanzanite Tanzanite

Glassy and lustrous gem Tanzanite crystal that is very gemmy from top to bottom. Though small, it was selected from gem rough and has great overall form, color, and transparency. Natural, unheated gem Tanzanite crystal, 1.7 x 0.7 x 0.5 cm.

AF136 - Tanzanite  sold

Merelani Hills, Tanzania
Thumbnail - 2.2 x 1.4 x 0.9 cm



(click on an image to enlarge)

Tanzanite Tanzanite Tanzanite

Glassy and lustrous gem Tanzanite crystal, complete high quality crystal. Natural, unheated gem Tanzanite crystal, 2.2 x 1.4 x 0.9 cm.


AF137 - Tanzanite   $2,500  available

Merelani Hills, Tanzania
Thumbnail - 2.5 x 2 x 1.1 cm



(click on an image to enlarge)

Tanzanite Tanzanite Tanzanite

Glassy and lustrous gem Tanzanite crystal, complete high quality crystal. Natural, unheated gem Tanzanite crystal, 2.5 x 2 x 1.1 cm.

AF401 - Spinel with Pargasite  sold

Mahenge, Tanzania
Small Cabinet - 8 x 6 x 5 cm



(click on an image to enlarge)

Spinel with Pargasite Spinel with Pargasite Spinel with Pargasite Spinel with Pargasite Spinel with Pargasite

Large red Spinel from Mahenge. Spinels from this locality are rare on the specimen market because the vast majority are cut up a gems, which are spectacular from this locality. This is a large octahedral crystal of good color and the addition of the green Pargasite makes for an attractive specimen. Lots of small gemmy areas as can be seen in the lower photo - this would cutmany small stones if broken up which I estimate would retail for at least the price of the specimen.


AF402 - Tsavorite on Pyrite  sold

Merelani Hills, Lelatema Mtns., Arusha Region, Tanzania
Small Cabinet - 6 x 3.5 x 3.5



(click on an image to enlarge)

Tsavorite on Pyrite Tsavorite on Pyrite Tsavorite on Pyrite

Rare matrix Tsavorite specimen with crystals to 2cm across set in Pyrite. The Tsavorites have good luster and nice mint green color. Matrix Tsavorites are very hard to come by, this one with big crystals that contrast nicely against the Pyrite.


AF403 - Tsavorite  sold

Merelani Hills, Lelatema Mtns., Arusha Region, Tanzania
Thumbnail - 2.2 x 2.1 x 1.3



(click on an image to enlarge)

Tsavorite Tsavorite Tsavorite Tsavorite

Superb single Tsavorite crystal, glassy and undamaged with top green color and luster. Lots of transparency and classic form, a very good crystal, the best Tsavorite I have ever offered.

AF404 - Tsavorite with Tanzanite  sold

Merelani Hills, Lelatema Mtns., Arusha Region, Tanzania
Thumbnail - 2.3 x 2 x 1.8



(click on an image to enlarge)

Tsavorite with Tanzanite Tsavorite with Tanzanite Tsavorite with Tanzanite

Good sized (1.7cm) Tsavorite that is also very complete and uniform in shape set in matrix of Tanzanite and Graphite. The Tsavorite has great color and would make a great specimen on it's own, but the association with the Tanzanite makes this one special.


AF405 - Spessartine with Mica  sold

Loliondo, Arusha Region, Tanzania
Thumbnail - 1.6 x 1.6 x 1.5



(click on an image to enlarge)

Spessartine with Mica Spessartine with Mica Spessartine with Mica Spessartine with Mica

Gemmy, citrus orange single Spessartine, complete and undamaged and also free of any black inclusions that seem to plague most of these. These occur in fine grained Mica, so the larger crystals attached to this one are both visually appealing and a little unusual.

AF406 - Enstatite  sold

Kilosa, Tanzania
Thumbnail - 1.8 x 1.5 x 0.8



(click on an image to enlarge)

Enstatite Enstatite

Facet grade Enstatite crystal with good formcompared to most I see from this locality, which are usually best suited for faceting. This crystal has good faces all around except one on the backside which has some irregularities.


AF407 - Magnesio-axinite  sold

Merelani Hills, Lelatema Mtns., Arusha Region, Tanzania
Thumbnail - 2.5 x 2.2 x 0.5



(click on an image to enlarge)

Magnesio-axinite Magnesio-axinite Magnesio-axinite

Gemmy pink and orange single crystal. Well crystallized on both sides with good transparency. The tip and lower left side have damage, but to even get a crystal of this quality is uncommon as the few pieces that do turn up are usually just shards.


AF408 - Magnesio-axinite  sold

Merelani Hills, Lelatema Mtns., Arusha Region, Tanzania
Thumbnail - 3 x 2.4 x 0.9



(click on an image to enlarge)

Magnesio-axinite Magnesio-axinite

Gemmy lavender and orange crystal portion with nice crystal faces on front and back.


AF409 - Alexandrite  sold

Lake Manyara, Arusha Region, Tanzania
Thumbnail - 0.9 x 0.5 x 0.25



(click on an image to enlarge)

Alexandrite Alexandrite

Small Alexandrite crystal with good form and good color change - green in sunlight and purple in incandescent light. Tabular shape that's complete and undamaged on all sides.

AF840 - Tanzanite  sold

Karo Pit, near Block D, Merelani Hills, Tanzania
Thumbnail - 2.1 x 0.8 x 0.7 cm



(click on an image to enlarge)

Tanzanite Tanzanite Tanzanite Tanzanite

Nearly flawless single crystal, it almost looks like a faceted gem. Thee are some growth marks on a few areas of the surface that appear to be where Graphite contacted the crystal, but they are just on the very surface. Rarely are Tanzanite crystals so gemmy. Thick, blocky crystal blue down one face and purple when viewed on the side. Natural, unheated gem Tanzanite crystal. 16.5 carats in weight, 2.1 x 0.8 x 0.7 cm.


AF984 - Diopside  sold

800 foot level, Karo Mine (extension off Block D), Merelani Hills, Arusha, Tanzania
Thumbnail - 2.9 x 0.9 x 0.6 cm



(click on an image to enlarge)

Diopside Diopside Diopside

Long, fully terminated deep green Diopside crystal. Great luster, complete all around and undamaged, size 2.9 x 0.9 x 0.6 cm.


AF988 - Grossular  sold

Merelani Hills, Arusha, Tanzania
Thumbnail - 1.4 x 1.4 x 1.2 cm



(click on an image to enlarge)

Grossular Grossular Grossular

Gem green Grossular crystal from the Tanzanite mines. Great luster, complete all around and undamaged, size 1.4 x 1.4 x 1.2 cm.

AF989 - Tremolite, Graphite on Tanzanite  sold

Merelani Hills, Arusha, Tanzania
Thumbnail - 2 x 1.3 x 1 cm



(click on an image to enlarge)

Tremolite, Graphite on Tanzanite Tremolite, Graphite on Tanzanite Tremolite, Graphite on Tanzanite

Tanzanite crystal with two attached green Tremolite crystals and Graphite crystals. Unusual combo I have not seen before, size 2 x 1.3 x 1 cm.

AF991 - Diopside  sold

800 foot level, Karo Mine (extension off Block D), Merelani Hills, Arusha, Tanzania
Miniature - 4.4 x 1 x 0.6 cm



(click on an image to enlarge)

Diopside Diopside Diopside

Long, fully terminated deep green Diopside crystal. Great luster, complete all around and undamaged, size 4.4 x 1 x 0.6 cm.

AF992 - Diopside  sold

800 foot level, Karo Mine (extension off Block D), Merelani Hills, Arusha, Tanzania
Miniature - 3.2 x 0.9 x 0.5 cm



(click on an image to enlarge)

Diopside Diopside Diopside

Long, fully terminated deep green Diopside crystal. Great luster, complete all around and undamaged with a Graphite crystal at base, size 3.2 x 0.9 x 0.5 cm.

AF999 - Diopside on Graphite  sold

800 foot level, Karo Mine (extension off Block D), Merelani Hills, Arusha, Tanzania
Thumbnail - 1.5 x 0.8 x 0.8 cm



(click on an image to enlarge)

Diopside on Graphite Diopside on Graphite Diopside on Graphite

Two criss-crossing transparent deep green Diopside crystals on a Graphite crystal. Great luster, complete all around and undamaged, size 1.5 x 0.8 x 0.8 cm.

G10 - Color change Garnet  sold

Madagascar
Thumbnail - 9.0 x 7.8 mm



(click on an image to enlarge)

Color change Garnet Color change Garnet

Heart shaped color change Garnet with a good color change from purple to blue. A superb collector item as this material is rare with only sporadic production. The Madagascar stones are know for rutile inclusions, which can be seen in this stone under magnification. 3.07 carats, $1500 per carat.


G11 - Color change Garnet  sold

Madagascar
Thumbnail - 10.8 x 5.6 mm



(click on an image to enlarge)

Color change Garnet Color change Garnet

Marquis shaped color change Garnet with a good color change from purple to blue. A superb collector item as this material is rare with only sporadic production. The Madagascar stones are know for rutile inclusions, which can be seen in this stone under magnification. 2.66 carats, $1000 per carat.


G12 - Umbalite Garnet  sold

Umba River Region, Tanzania
Thumbnail - 14.7 x 11.6 mm



(click on an image to enlarge)

Umbalite Garnet Umbalite Garnet

Raspberry red Garnet with superb color. A real attention getter of a gem with tons of eye appeal. Large sized stone that retains it's bright coloration (doesn't get too dark). 11.54 carats, $250 per carat.


G13 - Tsavorite  sold

Merelani Hills, Arusha, Tanzania
Thumbnail - 9.9 x 7.0 mm



(click on an image to enlarge)

Tsavorite Tsavorite Tsavorite

Fine, oval shaped Tsavorite with superb color saturation. Stunning color that would make a unique ringstone or a prestigious addition to a rare stone suite. 3.16 carats, $1503 per carat.


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