Gemstone Chart |
Natural Freshwater Pearl Freshwater pearls are a kind of pearl that comes from freshwater mussels.Freshwater pearls come in many shapes from round to button shapes, from flat flakes to rice shapes and in many colors. As with the salt water Akoya pearl the round shapes are generally more expensive. Color: orange, pink, white, gray, light purple, rose, black, brown, gold, yellow, silvery, green, blue, bronze. Categories: semi-precious stone Chemical Composition: CaCO3 Crystal Group: Not applicable Hardness: 3.5 - 4.0 Density: 2.66 ¨C 2.78+ Occurrence: China, Japan
| Natural Grossularite A member of the garnet group, grossularite is found in a variety of colors including, yellow, brown, white, colorless, green, violet-red, and orangey red. Color: Brown, yellow, green Categories: semi-precious stone Chemical Composition: Ca3Al2(SiO4)3 Crystal Group: Cubic Refractive Index: 1.72-1.748 Hardness: 7.25 Density: 3.65 Occurrence: Canada, East Africa, Pakistan, New Zealand, Ceylon, South Africa, U.S.A.
| Natural Idocrase Primarily a green color that will resemble jade.idocrase is one stone that is sometimes mistaken for jade by jewelers and consumers alike. Idocrase is from the greek and means mixed form, an allusion to its crystals showing a mixture of other mineral forms. Color: normally green, but also can be brown, yellow, blue and/or purple. Categories: semi-precious stone Chemical Composition: nesosilicate or sorosilicate Crystal Group: Tetragonal Refractive Index: 1.71 - 1.73 Hardness: 6.5 Density: 3.3 - 3.5 Occurrence: Quebec, Canada; California and the New England region of USA; Mt Vesuvius, Italy; Ural Mountains, Russia, Switzerland, East Africa
| Natural Jadeite A rare, usually green mineral of the pyroxene group. Jadeite can also occur in white, auburn, buff, or violet varieties. The most highly valued form of jade consists of jadeite.Jade has a history in China of at least four thousands years.Experts believe that, although more expensive, diamonds and gold cannot be compared with jade - jade is animated with a soul. Color: Pure white thru pink, brown, red, orange, yellow, mauve, violet, blue, and black, to an extensive range of green and mottled green and white. Categories: semi-precious stone Chemical Composition: NaAl(SiO3)2 Crystal Group: Monoclinic Refractive Index: 1.654 - 1.667 Hardness: 7 Density: 3.32 Occurrence: Northern Myanmar. Non commercial discoveries of Jadeite have also been reported in China; Russia (in the Polar Urals); Niigata, Japan; San Benito County, California, USA, and Guatemala.
| Natural Kornerupine Kornerupine is a rare mineral occasionally used as a gemstone. It appears frequently in parcels from Ceylon and may be confused with beryl, peridot, topaz, or quartz. Color: Brown, brownish red, yellow-green, light green, blue green Categories: semi-precious stone Crystal Group: Orthorhombic Refractive Index: 1.665 ¨C 1.683 Hardness: 6.5 Density: 3.25 - 3.35 Occurrence: Ceylon, Tanzania
| Natural Malaia Garnet Malaia garnet is a mixture of almandine, pyrope, and spessartine. It has remained the preserve of collectors for the 2 decades since it was discovered, mainly due to its extreme rarity.Tanzania is the known source for this lovely gemstone. Color: orangey pink, champagne, orange brown, copper-pink. Categories: semi-precious stone Chemical Composition: [Mg3 + Mn3]AL2(SIO4) Crystal Group: Cubic Refractive Index: 1.73 - 1.81 Hardness: 7 - 7.5 Density: 3.65 - 4.20 Occurrence: Kenya, Tanzania, Madagascar
| Natural Mali Garnet Mali Garnet is a mixture of grossular (calcium aluminum silicate) and andradite (calcium iron silicate ). It is a yellow-green variety of grossular with a slight overlap in the grossular-andradite series.Mali garnet is one of the latest discoveries in the garnet family. Color: yellow, brown, green. Categories: semi-precious stone Chemical Composition: Ca3Al2(SiO4)3 Crystal Group: Cubic Refractive Index: 1.72-1.748 Hardness: 7.25 Density: 3.65 Occurrence: Mali
| Natural Prehnite Prehnite is a hydrated calcium aluminum silicate that occurs in a soft yellow-green to apple-green color.It was a rare gemstone, most prehnite is translucent but transparent specimens are sometimes found.While you are unlikely to find it in your local jewelry store, gemstone dealers often have some supply. Deposits are found in South Africa, Australia, China, Scotland and the United States. Color: yellow green, brown, yellow brown, oil green Categories: semi-precious stone Chemical Composition: (CA2Al2SI3O10(OH)2) Crystal Group: Orthorhombic Refractive Index: 1.61 - 1.64 Hardness: 6 Density: 2.80 - 2.95 Occurrence: China, France, U.S.A., Scotland, Australia
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