Gemstone Chart |
Natural Actinolite Actinolite is a natural mineral with the chemical formula Ca2(Mg,Fe)5Si8O22(OH)2.the crystals have a hardness of 5.5 on Moh¡¯s scale, and there are two directions of cleavage. Natural actinolite is semi-precious to precious stone used in jewelry and other adornments. Color: Green, Brown Categories: semi-precious stone Chemical Composition: Amphibole Group Crystal Group: Monoclinic Refractive Index: 1.620 - 1.642 Hardness: 5.5 Density: 3.05 Occurrence: Tanzania
| Natural Agate Agate is a beautiful natural chalcedony stone, classified as a semi precious gem and has been used by people as early as the ancient Egyptians in and before 3000 BC! Agate is hard and tough enough to be incorporated into jewelry and other ornamental items. Color: Blue, green, yellow,orange, brown, gray Categories: semi-precious stone Chemical Composition: SiO2 Crystal Group: Hexagonal Refractive Index: 1.530 - 1.539 Hardness: 6.5 - 7 Density: 2.57 - 2.64 Occurrence: Scotland, U.S.A., India, England, Italy, Brazil, Uruguay, Germany, Egypt, Indonesia, and many other localities.
| Natural Andradite Andradite is a Garnet, belonging to the Garnet group. It has the most powerful luster of any garnet, and this makes it a reputable gem. Color: brown, greenish brown, yellowish green, green Categories: semi-precious stone Chemical Composition: Ca3Fe2(SiO4)3 Crystal Group: Cubic Refractive Index: 3.82 ¨C 3.85 Hardness: 6.5 Density: 1.888 ¨C 1.889 Occurrence: Mexico, Korea, Namibia, Russia, Iran, South Africa
| Natural Apatite Apatite displays strong fluorescence under short wave ultra-violet light. There is a particularly intense and deeply saturated, geenish-blue (aka swiss blue) variety from Madagascar known as "Neon Apatite" that is becoming quite popular in the gem trade. Color: yellow, green, below, violet Categories: semi-precious stone Chemical Composition: Phosphate group Crystal Group: Hexagonal Refractive Index: 1.63-1.64 Hardness: 5 Density: 3.17-3.23 Occurrence: Burma, Ceylon, Madagascar, Mexico, Canada, India
| Natural Beryl Beryl is a semi-precious clear gemstone which usually comes in greens, yellows, and occasionally pinks, ands various shades thereof. Color: Green, blue, pink, yellow, red Categories: semi-precious stone Chemical Composition: Be3Al2(SiO3)6 Crystal Group: Hexagonal Refractive Index: 1.577(+-.016), 1.583 (+-.017) Hardness: 7.5 Density: 2.67-2.745 Occurrence: Austria, Columbia, Brazil, Russia, East Africa, Australia, Madagascar, South Africa, Zimbabwe, India, Pakistan, Zambia, Nigeria, U.S.A., Afghanistan
| Natural Bi Color Tourmaline Bi color tourmaline is the name given to tourmaline which displays more than one color in the same cystal.It is classified as a semi-precious stone. Color: Green, red, yellow, orange. Brown, green, pink Categories: semi-precious stone Chemical Composition: (NaCa)(LI,MgFe,Al)9B3Si6(O,OH)31 Crystal Group: Hexagonal Refractive Index: 1.624(+.005, -.005) - 1.644(+.006, -.006) Hardness: 7-7.5 Density: 3.06 (.05, +.15) Occurrence: East Africa, Brazil, USA, Afghanistan, Nigeria, Madagascar
| Natural Chalcedony Chalcedony is a catch all term that includes many well known varieties of cryptocrystalline quartz gemstones. They are found in all 50 States, in many colors and color combinations, and in sedimentary, igneous, and metamorphic rocks. Color: grayish, purple, white, green, blue, lavender, yellow, brown Categories: semi-precious stone Chemical Composition: SiO2 Crystal Group: Hexagonal Refractive Index: 1.530 - 1.539 Hardness: 6.5 Density: 2.57 ¨C 2.64 Occurrence: Brazil, U.S.A. Germany, India, Uruguay, Austarlia, Egypt, Italy, Scotland, South Africa, Namibia, Madagascar, Mexico, Tanzania, and many other localities throughout the world.
| Natural Chrome Tourmaline Chrome tourmaline is a beautiful bottle-green variety of the gemstone. Gem-quality chrome tourmaline is quite pricey and is found in East Africa. Color: dark green, light green, yellowish green Categories: semi-precious stone Chemical Composition: (NaCa)(LI,MgFe,Al)9B3Si6(O,OH)31 Crystal Group: Hexagonal Refractive Index: 1.624(+.005, -.005) - 1.644(+.006, -.006) Hardness: 7-7.5 Density: 3.06 (.05, +.15) Occurrence: East Africa
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