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Gemstone Encyclopedia


Detailed information for any gemstone you are interested in.

0 Gemstone
Actinolite
Actinolite

Actinolite is a member of a series that contains varying amounts of ir...

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cuprian adamite - Greece
Adamite

Although adamite occurs in many localities, it's very rarely cut as a ...

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Agate

Agate is a variety of chalcedony that exists in many colors and is oft...

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albite - sri lanka and new mexico
Albite

Albite, usually colorless but sometimes yellow, pink, gray or reddish....

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natural alexandrite - engagement ring
Alexandrite

“Emerald by day, ruby by night,” alexandrite is well known for display...

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domeykite cabochons - algodonite
Algodonite

Bright, silvery metallic cabochons of algodonite and domeykite are att...

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almandine - Kenya
Almandine Garnet

Almandine is perhaps the most common garnet species. Forming series wi...

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amazonite carving - nine-tailed fox
Amazonite

A green to blue-green variety of microcline, amazonite makes a wonderf...

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triangle-cut amber - Mexico
Amber

Amber is the hardened resin of ancient pine trees. This organic substa...

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amblygonite - Myanmar
Amblygonite

Amblygonite gems are usually pale straw yellow. Although they are too ...

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oval Portuguese-cut amethyst - Georgia
Amethyst

Amethyst is crystalline quartz in colors ranging from pale lilac to de...

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Ametrine - Bolivia 24.64 cts
Ametrine

Ametrine is a variety of quartz that displays bands of both amethyst p...

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pendant
Ammolite

Ammolite is a rare, iridescent, gem-quality material cut from the foss...

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Analcime
Analcime

Large colorless crystals of Analcime are a great rarity although small...

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brilliant-cut anatase - Brazil
Anatase

Anatase occurs in many beautiful colors, such as deep indigo and amber...

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round brilliant andalusite - Brazil
Andalusite

Strongly pleochroic, andalusite can show shades of green, brown, and r...

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andesine
Andesine

These feldspars are rarely encountered in gem form. Andesine's occurre...

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brilliant-cut andradite - Mexico
Andradite

Andradite is one of the most sought after garnet species. Although mor...

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Portuguese-Cut Anglesite - Morocco
Anglesite

Although anglesites with pale colors can show great dispersion and bri...

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anhydrite - Germany
Anhydrite (Angelite)

Rare and difficult to cut, anhydrite is seldom faceted. However, this ...

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square-cut anorthite - Japan
Anorthite

The rarest plagioclase feldspar, anorthite is very rarely faceted.

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neon blue-green apatite
Apatite

Although too brittle for most jewelry use, properly cut apatite gems a...

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faceted apophyllite
Apophyllite

Although not suitable for jewelry, apophyllite is a popular collector'...

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oval-cut aquamarine - Brazil
Aquamarine

Named after the color of sea water, aquamarine is the blue to blue-gre...

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aragonite - Czech Republic
Aragonite

Aragonite is more commonly found as a constituent of pearl and shell n...

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opalite jewelry - glass gemstones
Artisanal Glass

Glass has been used in jewelry for thousands of years. By itself, glas...

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triangle-cut augelite - California
Augelite

Soft and brittle, rare augelites are difficult to cut and unsuitable f...

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3.60 cts axinite, oval cut - Pakistan
Axinite

When faceted, the members of the axinite mineral group are usually int...

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azurite with malachite eyes - Bisbee, Arizona
Azurite

Collectors prize deep blue azurite crystals, but faceted gems are extr...

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Barite

Massive white barite (also called known as baryte) looks like marble a...

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Bayldonite
Bayldonite

Bayldonite is a nondescript greenish material that has been cut into c...

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benitoite trillion cut
Benitoite

With dispersion higher than diamond and sapphire-blue body color, beni...

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Beryl

The beryls are among the most popular, and also the most expensive, of...

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cushion-cut beryllonite - Brazil
Beryllonite

Difficult to facet and typically colorless, beryllonite is a rare coll...

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Bismutotantalite - Madagascar
Bismutotantalite

Extremely rare as a cut gem, even in very complete collections. Many o...

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1.15 Carat black round diamond James Allen
Black Diamond

Black is a color that can say a lot. Wearing black diamond jewelry com...

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bloodstone - Brazil
Bloodstone

Also known as heliotrope, bloodstone is the traditional March birthsto...

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1.50 Blue VS1 Fancy Color Pear Diamond Brian Gavin
Blue Diamond

Blue diamonds may be rare, but they have gained a big reputation over ...

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Boleite
Boleite

Cut boleite is strictly for collectors, since it is soft and very rare...

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square-cut boracite - Germany
Boracite

With light blue and green colors, no cleavage, and high hardness, bora...

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Bornite

Bornite is suitable only for cabochons. The bronzy color rapidly tarni...

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faceted brazilianite - Corrego Frio, Brazil
Brazilianite

Brazilianite's lovely green to yellow colors make it a must for gem co...

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Breithauptite
Breithauptite

Breithauptite is a curiosity cut for collectors, although it could be ...

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brookite - rectangular step cut, Pakistan
Brookite

Brookite usually occurs in very dark colors, transparent only in small...

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0.46 Carat dark brown princess diamond james allen
Brown Diamond

The most common of all fancy colors that can be expressed by diamonds ...

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step-cut brucite - South Africa
Brucite

Brucites are extremely difficult to cut. Although too soft for jewelry...

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freeform faceted bustamite - Australia
Bustamite

Pale pink and brownish red bustamite can make a very attractive facete...

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shield-cut bytownite - Mexico
Bytownite

Although bytownite occurs throughout the world, this feldspar variety ...

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pink conch pearl ring
Calcareous Concretions

Several species of marine mollusks produce stony growths called calcar...

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Calcite

Calcite is common and abundant throughout the world. The material has ...

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Canasite

The material usually seen on the market as “canasite” is purplish in c...

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Cancrinite

Cancrinite is one of the most attractive of all opaque or translucent ...

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carnelian
Carnelian

The best-known and generally least expensive variety of chalcedony is ...

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brilliant-cut cassiterite - Bolivia
Cassiterite

Cassiterite is a durable gemstone with tremendous dispersive fire, esp...

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Catapleiite
Catapleiite

The only reported cut catapleiite is from Mte. Ste. Hilaire, Quebec, C...

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custom cushion-cut celestite - Madagascar
Celestite

Soft, fragile, and hard to cut, celestite or celestine is seldom seen ...

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ceruleite cabochon - Chile
Ceruleite

A little-known gem material of truly exquisite color, sky-blue cerulei...

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radiant-cut cerussite - Namibia
Cerussite

As beautiful as a diamond, a faceted cerussite actually has higher dis...

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chabazite - Nova Scotia
Chabazite

Although faceting chabazite isn't too difficult, it's too soft for jew...

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Chalcedony

Technically, chalcedony (kal SED' uh nee) is any form of microcrystall...

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Chambersite

Chambersite is an exceedingly rare mineral. Although it has properties...

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1.50 Carat round diamond
Chameleon Diamond

Professionals will tell you never to trust a trade name used to descri...

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cabbed charoite
Charoite

With light to medium dark purple colors and swirling patterns, charoit...

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chicken-blood stone statue
Chicken-Blood Stone

One of the most prized ornamental materials in China, chicken-blood st...

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Childrenite

Cut childrenite is a great rarity, and all gems are small. Cut eosphor...

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rectangular step-cut chiolite - Greenland
Chiolite

Chiolite makes a challenging gem. It's difficult to cut, extremely rar...

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Chromite
Chromite

Chromite is shiny and black, and makes a curious-looking cabochon with...

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cat's eye chrysoberyl - Sri Lanka
Chrysoberyl

Although many gems show a cat’s eye effect, when the term “cat’s eye” ...

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chrysocolla specimens
Chrysocolla

Pure blue chrysocolla is extremely soft but interesting to gem collect...

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chrysocolla chalcedony - Arizona
Chrysocolla Chalcedony

Marketed as "Gem Silica" this relatively rare, blue to blue-green, opa...

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chrysoprase carving
Chrysoprase

Chrysoprase is apple-green chalcedony that derives its color from nick...

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cinnabar - Nevada
Cinnabar

Magnificent red cinnabar is extremely soft and fragile, so faceted mat...

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pear-cut citrine
Citrine

Citrine is the yellow to red-orange variety of crystalline quartz. Cle...

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Grossular Clinochlore
Clinochlore

Clinochlore is a family of minerals in the chlorite group. To date, on...

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cobaltite sphere
Cobaltite

Cobaltite cabochons can have a lovely metallic luster. However, this g...

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colemanite - round brilliant cut
Colemanite

Colemanite is an abundant mineral, and transparent material isn’t rare...

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color change garnet - Tanzania
Color Change Garnet

Any stone that changes color under different types of light is a rare ...

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Finished version of Emerald Cut Color Change Sapphire
Color Change Sapphire

Color change sapphires are those that change color between light sourc...

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coral carvings
Coral

Coral is the external skeleton of a tiny, plant-like marine animal cal...

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Cordierite

The crystal structure of cordierite has many similarities to that of b...

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Corundum

Next to diamond, corundum is the hardest mineral known and is very com...

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covellite cabochon - Montana
Covellite

Although covellite has attractive blue colors and shows iridescence, t...

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Creedite

Probably fewer than a dozen creedite gems have ever been faceted. This...

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baguette-cut crocoite - Tasmania
Crocoite

Lovely saffron-colored crocoite is quite a rare mineral. Although too ...

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oval-cut cryolite
Cryolite

Typically colorless with a “sleepy” look, cryolite is rarely found in ...

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Octagonal-cut cuprite - Namibia
Cuprite

One of the rarest of all facetable gems, cut cuprites can show magnifi...

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cushion-cut danburite - Madagascar
Danburite

A very durable gemstone, danburite is an excellent choice for jewelry ...

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light yellow datolite - Russia
Datolite

Polished and sliced datolite nodules can show off very attractive colo...

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demantoid garnet - cushion cut, Madagascar
Demantoid Garnet

One of the rarest garnet varieties, demantoid can have a green color t...

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faceted diamond - South Africa - 69
Diamond

Diamond is the most romanticized and heavily marketed of all gemstones...

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diaspore - Turkey
Diaspore

Diaspore is hard enough to make a durable jewelry stone, but the typic...

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Dickinsonite

This mineral is seldom even mentioned in the gem literature because it...

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faceted diopside gems
Diopside

Violane has been used for beads and inlay—transparent material is alwa...

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dioptase faceted by Mark Kaufman - Namibia
Dioptase

Dioptase has a beautiful, emerald-like green color. Although this mine...

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dolomite - trillion cut
Dolomite

Although transparent dolomite crystals are fairly abundant and popular...

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dumortierite - Nevada and California
Dumortierite

Dumortierite is a beautiful and very hard material, eminently suitable...

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rectangular mix-cut ekanite - Sri Lanka
Ekanite

A relative newcomer to the world of gemstones, ekanite is rare and usu...

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Princess of Carolina
Emerald

Emerald has been synonymous with the color green since ancient times. ...

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Enstatite

Most gem enstatites have indices in the range 1.663-1.673. The brown a...

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eosphorite - shield cut
Eosphorite

Faceted eosphorites in pale colors are quite attractive and easy to cu...

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epidote - Pakistan
Epidote

The epidote mineral supergroup contains many related species of intere...

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Ettringite
Ettringite

Ettringite is not generally facetable. Any cut stone would be consider...

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oval-cut euclase - Brazil
Euclase

Although hard enough to be worn safely in jewelry, euclase in beautifu...

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oval-cut eudialyte - Canada
Eudialyte

Although lapidaries can cut cabochons and decorative objects from mass...

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Euxenite
Euxenite

Euxenite is seldom seen in collections. Most collectors would not rega...

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Polished Samples of Plagioclase
Feldspar

Feldspars are the most common minerals at the Earth's surface. In fact...

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Fergusonite
Fergusonite

This mineral is not abundant and is known from various localities. Cab...

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pink fluorite - Pakistan
Fluorite

Although too fragile for most jewelry use, fluorites are often faceted...

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flower brooch with freshwater pearl petals
Freshwater Pearl

Like their marine cousins, many freshwater mollusks can produce pearls...

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cushion-cut friedelite - New Jersey
Friedelite

Friedelite is not abundant, and gem-quality material is rarely seen ev...

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Gadolinite
Gadolinite

This is not a terribly attractive gemstone, but faceted gems would be ...

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gahnospinel pair - Nigeria
Gahnospinel

Gahnospinel is a solid-state solution between spinel and gahnite.

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spessartite garnet, triangle cut - Nigeria
Garnet

Although commonly associated with the color red, garnets can be found ...

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Gaylussite
Gaylussite

This mineral is very hard to cut because of extreme softness and cleav...

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grandidierite cabochon
Grandidierite

A rather rare mineral, lovely blue-green grandidierite is seldom seen ...

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1.25 Carat round diamond James Allen
Gray Diamond

Diamonds with a pure gray hue are a rare treasure indeed. More often, ...

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1.40 Carat round diamond Fancy Intense Green James Allen
Green Diamond

Green diamonds are the oddballs of the fancy colored diamond varieties...

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Merelani Mint Garnet - Grossular - Tanzania
Grossular Garnet

Grossular garnets come in almost every color, even colorless, except b...

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step-cut gypsum - Peru
Gypsum

Gypsum is one of the most abundant minerals, but gem-quality crystals ...

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baguette-cut hambergite - Myanmar
Hambergite

Although hard enough for jewelry use, rare hambergite is a gem for col...

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round haüyne - Germany
Haüyne

One of the major mineral constituents of lapis lazuli, haüyne is rarel...

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trilliant-cut heliodor
Heliodor

Heliodor is a member of the beryl family. This stone is known for its ...

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marquise-cut hematite
Hematite

Hematite has a long history of use as a pigment. As a gemstone, this m...

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hemimorphite cabochon - Arizona
Hemimorphite

Massive hemimorphite can have a very delicate, blue color. However, it...

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herderite - Brazil
Herderite

Herderite is a rare collector's gem, especially in larger sizes. Altho...

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hessonite garnet - cushion cut, Tanzania
Hessonite

Also known as the “cinnamon stone,” hessonite is the yellow-orange to ...

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Hodgkinsonite

Hodgkinsonite is one of the rarest of all collector gems. Cut stones a...

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Holtite

This mineral was first noted in 1937 but was not described in detail u...

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Howlite

Howlite is always opaque in nodules; it is an abundant material and ea...

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huebnerite - Peru
Huebnerite (Hübnerite)

It should not be difficult to find numerous small faceted huebnerites ...

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cushion-cut clinohumite - humite group series
Humite

Clinohumites and chondrodites can make beautiful gemstones with rich c...

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hureaulite - Brazil
Hureaulite

Hureaulite can show rich and lively pink, rose, and orange colors. How...

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hurlbutite - crystal pair - New Hampshire
Hurlbutite

Hurlbutite is an extremely rare mineral. Minute, colorless faceted sto...

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hydrogrossular garnet cabochon - Peru
Hydrogrossular Garnet

Hydrogrossular differs from the other garnets in that it is never tran...

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Hyperitdiabas

Hyperitdiabas is one of the most outstanding minerals I have encounter...

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Idocrase (Vesuvianite)

Idocrase is one of the lesser known and more beautiful collector gems....

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Inderite
Inderite

Inderite is very soft and difficult to cut, and only a few stones have...

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Iolite

This stone, which represents one of the few relatively available and a...

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jadeite, diamond, and white gold ring
Jadeite

One of two distinct minerals commonly known as jade, jadeite is the ra...

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Jasper - Oregon
Jasper

Jasper is an opaque, solid or patterned variety of cryptocrystalline q...

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0.80-ct Jeremejevite - Namibia
Jeremejevite

Jeremejevite would make a durable and attractive jewelry stone, but th...

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jet cuff
Jet

Historically a popular black gem, jet has declined in popularity in mo...

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Kornerupine

Star kornerupine also has been found (Mogok, Myanmar) but is very rare...

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Rectangular-cut kurnakovite
Kurnakovite

Kurnakovite is difficult to cut, inadvisable to wear, and usually colo...

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kyanite - Nepal
Kyanite

Kyanite’s physical properties make it very difficult to facet. However...

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Kämmererite
Kämmererite

A beautiful but rare mineral, kämmererite is extraordinarily difficult...

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Labradorite
Labradorite

An overview on Labradorite Jewelry and Gemstones. Covers details and e...

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langbeinite - New Mexico
Langbeinite

This material is nondescript and is cut solely as a curiosity. The gem...

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lapis lazuli cuff links
Lapis Lazuli

Lapis lazuli has been used since ancient times and remains popular tod...

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Laserblue synthetic glass
Laserblue

Laserblue is a rare, synthetic glass. It's hard for glass but easy to ...

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Lawsonite
Lawsonite

Lawsonite is extremely rare as a faceted stone, seldom reported and ge...

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oval-cut lazulite - Pakistan
Lazulite

Lazulite makes a magnificent, deep blue gemstone. Although the mineral...

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0.68-ct rectangular step-cut legrandite
Legrandite

Too soft for jewelry use, legrandite is a popular collector’s mineral ...

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Lepidolite
Lepidolite

Reddish granular or massive lepidolite is usually slabbed for ornament...

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Pear-cut leucite - Italy
Leucite

Although abundant in various lava rocks, leucite is extremely rare in ...

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Linarite
Linarite

The blue color of linarite is magnificent, and it is a pity that large...

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step-cut ludlamite - Idaho
Ludlamite

Ludlamite has a lovely green color, but cut stones are extremely rare....

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polished mangesite sphere
Magnesite

Transparent, gem-quality magnesite is rare and beautiful, with colors ...

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malachite carving
Malachite

Malachite is a beautiful decorative stone. Its rich, patterned colorat...

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Barion-cut malaia garnet
Malaia Garnet (Malaya Garnet)

Malaia or malaya garnets are typically light to dark, slightly pinkish...

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cushion-cut Mali garnet
Mali Garnet

One of the rarer varieties in the garnet group, Mali garnet is a blend...

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faceted mandarin garnet - Namibia
Mandarin Garnet

While the colors of spessartite garnet gemstones cover a wide range of...

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Manganotantalite

Manganotantalite makes a spectacular red brown gem that is a very rare...

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marcasite - Canada
Marcasite

Marcasite has a long history of use as a decorative and jewelry materi...

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Meliphanite

Meliphanite is an extremely rare gemstone, and perhaps fewer than 5-10...

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mellite pendant
Mellite

Mellite is a rare and unusual organic gemstone. Although soft and frag...

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A cluster of microcline twinned crystals
Microcline

Microcline is a variety of feldspar. The only microcline you are likel...

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triangle-cut microlite - Brazil
Microlite

Ranging in color from pale yellow to brown, reddish, and green, microl...

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oval-cut milarite - Brazil
Milarite

Very rare milarite crystals can occur in green and yellow colors. Tran...

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millerite - filiform crystals
Millerite

Millerite has a rich, attractive yellow color. Massive millerites can ...

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shield-cut mimetite - Namibia
Mimetite

Transparent mimetite crystals are extremely rare, and very few have ev...

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moldavite, Curtains cut
Moldavite

An olive to bottle-green natural glass, moldavite is a rare material p...

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Monazite
Monazite

Monazite may be partially metamict, with N=1.79. Stones can be an attr...

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custom-carved moonstone by Tom Munsteiner - Tanzania
Moonstone

Found all over the world, moonstone is prized for its blue to white ad...

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Mordenite
Mordenite

Compact, fibrous material is cabbed because the fibers provide a chato...

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morganite - triangular cushion cut
Morganite

A member of the beryl family, morganite shows a range of pink colors d...

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Nambulite
Nambulite

The color of Namibian nambulite is a striking orange-red, very intense...

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Natrolite, Mesolite, Scolecite

All three minerals are fibrous or elongated zeolite minerals. Faceted ...

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indochinite tektite
Natural Glass

Glass comes in several natural forms. All are used in jewelry.

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Nepheline
Nepheline

A variety called elaeolite is red, green, brown, or gray, massive or i...

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jade dagger hilt - India
Nephrite

Nephrite is one of the two distinct minerals commonly known as jade. W...

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Neptunite
Neptunite

An overview on Neptunite Jewelry and Gemstones. Covers details and ess...

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niccolite - rough and cabochon
Niccolite (Nickeline)

Niccolite’s delicate peachy red color and metallic luster looks beauti...

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obsidian cabochon - Brazil
Obsidian

Obsidian is the most common form of natural glass and occurs in many a...

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Oligoclase

Oligoclase gems are feldspars that are part of a solid state series be...

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cabbed onyx - Brazil
Onyx

For millennia, artisans have carved intricate cameos from black-and-wh...

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Ethiopian opal, faceted by Mark Kaufman - opal gems
Opal Stone

Opals are in a class by themselves. As a species, opal is so unique it...

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orange fancy colored diamonds brian gavin
Orange Diamond

Quite a few diamonds on the market display orange as part of a multi-h...

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Oregon sunstone, custom cut with schiller
Oregon Sunstone

While feldspar sunstones from sources around the world have been used ...

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Rough orthoclase
Orthoclase

Orthoclase is best known for moonstone. It is occasionally a transpare...

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pear-cut padparadscha sapphire
Padparadscha Sapphire

Padparadscha sapphires show a blend of orange and pink colors, one of ...

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cushion-cut painite - Myanmar
Painite

Until 2001, only three painite crystals were known to exist. Since the...

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Palygorskite - Virginia
Palygorskite

Although marketed as “angel skin opal,” “rock wood,” and “mountain lea...

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papagoite cabochon - Arizona
Papagoite

Cerulean blue papagoite crystals are too small for faceting. However, ...

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cushion-cut paraíba tourmaline - Mozambique
Paraíba Tourmaline

Discovered in 1989, paraíba tourmalines are among the world’s most pri...

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Pargasite
Pargasite

The amphibole group is very large and extremely complex and contains n...

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faceted parisite - Pakistan
Parisite

More well-known as rare inclusions in emeralds, parisite crystals are ...

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natural pearl
Pearl

Pearls are the only gems found within living creatures, both salt and ...

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Larimar cabochon - Dominican Republic
Pectolite (Larimar)

Fibrous pectolite has long been a curiosity for gem collectors. Compac...

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Pentlandite
Pentlandite

Pentlandite resembles other yellowish metallic minerals and is cut by ...

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Periclase - synthetic
Periclase

Periclase has been synthesized in large masses in the laboratory, but ...

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peridot - Mogok, Myanmar
Peridot

The modern August birthstone, peridot has been prized as a jewelry sto...

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peristerite
Peristerite

Peristerite is primarily oligoclase with a complex mixture of feldspar...

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perthite
Perthite

Perthite is a blend of microcline, albite and oligoclase. It is usuall...

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petalite - Afghanistan
Petalite

Gem-quality, colorless, facetable petalite is rare and desirable to co...

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faceted phenakite - Russia
Phenakite

Rare phenakite is a very hard gem material suitable for jewelry. Usual...

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rectangular-cut phosgenite - Namibia
Phosgenite

Rare phosgenite typically shows pale colors. This material is difficul...

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Faceted phosphophyllite, 10.22 cts - Bolivia
Phosphophyllite

Renowned for its delicate blue-green shades, phosphophyllite’s beauty ...

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Pink I1 Fancy Color Pear Diamond Brian Gavin
Pink Diamond

Pink diamond is one of nature’s rarest beauties. Often found in small ...

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oval-cut pollucite - Afghanistan
Pollucite

Colorless pollucites lack fire when cut and are usually small. However...

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Powellite
Powellite

An overview on Powellite Jewelry and Gems. Covers details and essentia...

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Prehnite

Prehnite is popular as a cabochon material among hobbyists because of ...

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prosopite cabochon - Zacatecas, Mexico
Prosopite

Prosopite is usually a nondescript mineral with no gem significance. H...

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proteus garnet
Proteus

A few almandine/pyrope garnets from the US will change with treatment ...

Gem Profile
faceted proustite - 2.58 cts
Proustite

Proustite crystals have magnificent red colors and good brilliance. Al...

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Pumpellyite

The gem variety of pumpellyite, chlorastrolite, is best known from the...

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0.23 Purple VS2 Fancy Color Cushion Diamond Brian Gavin
Purple Diamond

Purple is a powerful color that historically has been linked with wisd...

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purpurite cabochon
Purpurite

Purpurite is too soft for jewelry wear and never transparent. Neverthe...

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pyrargyrite cabochon - South Africa
Pyrargyrite

Deep red pyrargyrite occurs in a number of localities in well-formed b...

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Pyrite
Pyrite

Pyrite is more commonly known as fool’s gold and is familiar to nearly...

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grape pyrope garnet - Congo
Pyrope Garnet

Pyrope always occurs in series with other garnet species. Common, dark...

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Pyrophyllite
Pyrophyllite

Pyrophyllite resembles talc in many ways and is indistinguishable by e...

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freeform step-cut pyroxmangite - Brazil
Pyroxmangite

Pyroxmangite grains are rare, seldom clean enough to facet, and diffic...

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Pyrrhotite
Pyrrhotite

An overview on Pyrrhotite Jewelry and Gemstones. Covers details and es...

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Quartz, Tibet
Quartz

An overview on Quartz Jewelry and Gemstones. Covers details and essent...

Gem Profile
Quartzite
Quartzite

Quartzite is a rock made up of tightly packed quartz grains. Sometimes...

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realgar - wheel of light pendant
Realgar

Although this common arsenic sulfide mineral occurs worldwide, cut gem...

Gem Profile
navette-cut red beryl - Utah
Red Beryl

Originally known as bixbite, red beryl is one of the rarest, most desi...

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fancy purplish red diamond james allen
Red Diamond

The discovery of any fancy-colored diamond is an exceedingly rare and ...

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oval-cut rhodizite - Madagascar
Rhodizite

Rhodizite is tough enough to make an excellent jewelry stone. However,...

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faceted rhodochrosite - South Africa
Rhodochrosite

Beautiful rose red to pink rhodochrosite crystals are popular with min...

Gem Profile
round brilliant rhodolite - Tanzania
Rhodolite Garnet

Rhodolites are purplish red garnets, a blend between almandine and pyr...

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faceted rhodonite - Brazil
Rhodonite

Ranging in color from pink to a fine rose red, rhodonite is a popular ...

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rose quartz - heart cut
Rose Quartz

A popular variety of colored quartz, rose quartz makes a durable jewel...

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faceted rubellite - Nigeria
Rubellite

Rubellites are tourmalines with reasonably saturated dark pink to red ...

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rectangular step-cut ruby - Mozambique
Ruby

One of the most popular traditional jewelry stones, ruby is exceptiona...

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cushion-cut rutile - Pakistan
Rutile

Though perhaps best known as inclusions within other gems, rutile crys...

Gem Profile
saltwater pearls - diamond brooch
Saltwater Pearl

Although pearls are one of humanity’s most ancient gems, natural under...

Gem Profile
samarskite - Norway
Samarskite

Samarskite is a very heavy material from which lustrous black to brown...

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Sanidine

Sanidine is a mineral of volcanic rocks, rarely considered a gem. Whil...

Gem Profile
triangle mixed-cut sapphire - Sri Lanka
Sapphire

Few gems have held our attention over millennia as well as sapphire. T...

Gem Profile
sapphirine - Sri Lanka
Sapphirine

Sapphirines are durable but very rare gemstones. Although named after ...

Gem Profile
faceted sarcolite - Italy
Sarcolite

Sarcolite is an extremely rare mineral. Tiny, colorless to “fleshy pin...

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scapolite, shield cut with concave facets
Scapolite

Although not well known, scapolite would make an attractive gem materi...

Gem Profile
oval-cut scheelite - China
Scheelite

Large, faceted scheelites are among the most beautiful of all collecto...

Gem Profile
faceted scorodite - Namibia
Scorodite

With lovely colors and intense pleochroism, faceted scorodite is a pri...

Gem Profile
Sellaite
Sellaite

An overview on Sellaite Jewelry and Gemstones. Covers details and esse...

Gem Profile
Senarmontite
Senarmontite

Senarmontite is a rare mineral, restricted in occurrence to the presen...

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rectangle-cut serandite - Canada
Serandite

To date, only one locality — Mont St. Hilaire, Quebec, Canada — has pr...

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williamsite - New Jersey
Serpentine

The gem material known as serpentine actually encompasses several rela...

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Shattuckite
Shattuckite

Shattuckite is often mixed with quartz, and data often reported for pr...

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Shortite

Shortite is an exceedingly rare, not overly attractive mineral. Cut ge...

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Brazilian siderite - faceted
Siderite

Siderite is difficult to cut, but this light brown collector's gem has...

Gem Profile
Sillimanite

The fibrolite from Burma and Sri Lanka is well known to gem collectors...

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Simpsonite

Simpsonite is an extremely rare gemstone. The material from Western Au...

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Sinhalite

Long thought to be brown peridot, sinhalite was investigated in 1952 a...

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Smaltite
Smaltite

Smaltite is a collectors oddity, cut only as cabochons. It is seldom s...

Gem Profile
bi-color smithsonite cab - Mexico
Smithsonite

Smithsonite occurs across the globe, but facetable crystals are extrem...

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Smokey Quartz
Smoky Quartz

Smoky quartz comes in every shade of brown, from a light tan to nearly...

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sodalite carving
Sodalite

Typically blue, durable, and easy to cut, sodalite is highly desired b...

Gem Profile
Sogdianite

Sogdianite is an extremely rare mineral, suitable for cabochons. The c...

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oval brilliant spessartite garnet - Mozambique
Spessartite Garnet

Usually orange to reddish brown, gem-quality spessartite or spessartin...

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Cushion-cut sphalerite - Montana
Sphalerite

Sphalerite occurs in many colors. With a dispersion over three times t...

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Sphene - Emerald Cut - Madagascar
Sphene (Titanite)

Sphene, also known as titanite, has rich body colors, strong trichrois...

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round spinel
Spinel

Although long known best for being misidentified as ruby, spinel is a ...

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bicolor spodumene
Spodumene

Extraordinarily difficult to cut, spodumene has several colorful varie...

Gem Profile
oval-cut spurrite - Japan
Spurrite

An attractive but uncommon mineral, spurrite has seldom been cut as a ...

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Star Sapphire
Star Sapphire

Star sapphire is a type of sapphire that displays asterism, a star-lik...

Gem Profile
reddish brown staurolite - oval cut, Brazil
Staurolite

Staurolite crystals in opaque cross shapes are popular gemstones. Howe...

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faceted stibiotantalite - Mozambique
Stibiotantalite

Rare stibiotantalite possesses an interesting mix of physical and opti...

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Stichtite

Stichtite is not facetable, but the pink color is quite striking in ca...

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Stolzite
Stolzite

Stolzite is a rare mineral; much rarer than wulfenite and usually occu...

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Strontianite

Strontianite is a collector’s oddity, with no spectacular properties t...

Gem Profile
faceted sugilite by Mark Oros
Sugilite

What is the color of sugilite? Grape jelly purple is a good descriptio...

Gem Profile
faceted sulfur - Michigan
Sulfur (Sulphur)

Although sulfur is very abundant, facetable material is not. Sulfur is...

Gem Profile
Oligoclase Sunstone from ndia
Sunstone

Sunstones contain hematite or goethite inclusions, which reflect light...

Gem Profile
Taaffeite

Taaffeite reacts to most gemological tests like mauve-colored spinel, ...

Gem Profile
Talc
Talc

An overview on Talc Jewelry and Gemstones. Covers details and essentia...

Gem Profile
Tantalite
Tantalite

Tantalite is too dark to be of use as a faceted gem but is sometimes c...

Gem Profile
triangle-cut tanzanite
Tanzanite (Zoisite)

Tanzanite has had a rapid rise to prominence among jewelers and gem en...

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Libyan desert glass - tektite - Egypt
Tektite

Tektite is a natural glass formed from the ejected debris of meteorite...

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Tephroite
Tephroite

Tephroite is generally reddish brown and barely translucent. However, ...

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thaumasite, rectangular step cut - South Africa
Thaumasite

For a long time, rare thaumasite crystals — pale, fragile, and with li...

Gem Profile
Thomsonite

Thomsonite cabochons take a high polish but are somewhat brittle. Thes...

Gem Profile
tiger's eye - South Africa
Tiger's Eye

Crocidolite, (blue asbestos,) alters to quartz, but while retaining it...

Gem Profile
silver-white topaz - Namibia
Topaz

The traditional November birthstone, topaz is a popular gem. Although ...

Gem Profile
bi-color tourmaline - Mozambique
Tourmaline

Tourmaline is a name applied to a family of related minerals with wide...

Gem Profile
Tremolite

It is possible to misidentify tremolite, mistaking it for other amphib...

Gem Profile
triphylite - triangular step cut
Triphylite (Tryphylite)

Triphylite is one of the world's rarest gems. The IGS had the extraord...

Gem Profile
cushion-cut tsavorite - Kenya
Tsavorite Garnet

An emerald-green variety of grossular garnet, tsavorite is one of the ...

Gem Profile
tugtupite cabochon
Tugtupite

Gem collectors prize tugtupite, the "Reindeer Stone," for its rich col...

Gem Profile
turquoises - Arizona and New Mexico
Turquoise

With striking sky blue to blue-green colors, turquoise has been prized...

Gem Profile
Ulexite
Ulexite

The fibrous material cuts interesting catseye cabochon gems, but they ...

Gem Profile
round faceted uvarovite - Canada
Uvarovite Garnet

Always a dark, rich green color, uvarovite is one of the rarest member...

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freeform vanadinite - Morocco
Vanadinite

Very few vanadinites have ever been cut. This is unfortunate, since th...

Gem Profile
double heart cabochon - Australia
Variscite

With beautiful green to blue-green colors and interesting patterns, va...

Gem Profile
villiaumite - Canada
Villiaumite

A little-known and rare collector’s gemstone, villiaumite is very diff...

Gem Profile
rectangle-cut vivianite - Bolivia
Vivianite

Vivianite is so fragile and soft, any faceted gems would be difficult ...

Gem Profile
oval mixed-cut väyrynenite - Pakistan
Väyrynenite

Väyrynenite is a very rare mineral. Crystals as well as faceted gemsto...

Gem Profile
Wardite
Wardite

Wardite is another of the many phosphates that have been cut by collec...

Gem Profile
Wavellite

Wavellite is a very attractive mineral, well-known to collectors. Its ...

Gem Profile
faceted weloganite
Weloganite

Truly a collector’s gem, weloganite is very rare and seldom cut. This ...

Gem Profile
faceted whewellite - Czech Republic
Whewellite

Seldom seen even in mineral collections, whewellite is very rarely fac...

Gem Profile
Wilkeite
Wilkeite

An overview on Wilkeite Jewelry and Gemstones. Covers details and esse...

Gem Profile
shield-cut willemite - Namibia
Willemite

Willemite is prized for its intense green fluorescence. Too fragile fo...

Gem Profile
faceted witherite - England
Witherite

Easy to cut but too soft and fragile for jewelry, a faceted witherite ...

Gem Profile
Wollastonite
Wollastonite

Interesting cabochons have been cut from wollastonite, especially from...

Gem Profile
emerald-cut wulfenite - Red Cloud Mine
Wulfenite

Although aesthetically magnificent wulfenite crystals are often too th...

Gem Profile
Faceted xonotlite - Italy
Xonotlite

Xonotlite is strong and can take a good polish. However, these gems ar...

Gem Profile
1.92 Carat round diamond James Allen
Yellow Diamond

When someone mentions diamonds, the first image that most people think...

Gem Profile
faceted yugawaralite
Yugawaralite

Yugawaralite is a very rare colorless to pinkish zeolite mineral. Litt...

Gem Profile
faceted zektzerite, 0.42 cts
Zektzerite

Small, cuttable crystals of very rare zektzerite are found only in a m...

Gem Profile
Zincite

Zincite is a very rare mineral. It’s also difficult to cut, which make...

Gem Profile
yellowish oval-cut zircon
Zircon

Don’t be confused by the name. Zircon is a natural, magnificent, and u...

Gem Profile
Zunyite

An overview on Zunyite Jewelry and Gemstones. Covers details and essen...

Gem Profile

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