Gemstone Chart |
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 – 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 Chrysoberyl The Chrysoberyl family is best known for the more valuable alexandrite and catseye varieties. Faceted chrysoberyl is a beautiful gem which is not as well known in its own right. Apart from the high hardness, it takes a good polish and has a good luster. Color: yellow, green, color changing, red, blue-green, greenish-yellow or brown Categories: semi-precious stone Chemical Composition: BeAl2O4 Crystal Group: Orthorhombic Refractive Index: 1.741 - 1.760 Hardness: 8.5 Density: 3.73 Occurrence: Ceylon, Tanzania, Russia, Madagascar, Brazil.
| Natural Chrysoberyl Cats Eye Chrysoberyl cats eye is a very rare and expensive gemstone which is found in small quantities in Sri-Lanka and Brazil. The cats eye is present because the stone has chatoyancy in its make up and this effect cause the ‘eye’ which moves as the gem is gently turned . Color: yellow, greenish yellow, yellowish green Categories: semi-precious stone Chemical Composition: BeAl2O4 Crystal Group: Orthorhombic Refractive Index: 1.741 - 1.760 Hardness: 8.5 Density: 3.73 Occurrence: Ceylon, Tanzania, Russia, Madagascar, Brazil.
| Natural Citrine Citrine is any quartz crystal or cluster that is yellow or orange in color. Although often cut as a gemstone, citrine is actually somewhat rare in nature. Color: Yellow, orange Categories: semi-precious stone Chemical Composition: SiO2 Crystal Group: Trigonal Refractive Index: 1.544-1.553 Hardness: 7 Occurrence: Brazil, Uruguay, Mexico, Russia, USA.
| Natural Emerald Emerald, the green variety of the mineral beryl, is the most famous and favored green gemstone.The majority of the worlds gem quality Emeralds come from the Muzo area of Colombia. Color: Blue, Green Blue Categories: precious stone Chemical Composition: Be3Al2(SiO3)6 Crystal Group: Hexagonal Refractive Index: 1.577(+-.016), 1.583 (+-.017) Hardness: 7.5-8 Density: 2.72 (-.05, +.12) Occurrence: Brazil, Pakistan,Russia, East Africa, India, Madagascar, Columbia
| Natural Euclase Euclase is a rare mineral, resembling beryl in color and hardness.Euclase is found in granitic pegmatites with other gem minerals such as topaz and beryl. Color: White, pale blue, greenish blue, dark blue. Categories: semi-precious stone Chemical Composition: BeAlSiO4(OH) Crystal Group: Monoclinic Refractive Index: 1.652-1.672 Hardness: 7.5 Density: 3.18 Occurrence: Brazil, Tanzania, Russia, Zimbabwe, Madagascar, Austria.
| Natural Hessonite Hessonite is one of the gem varieties of the garnet mineral, grossular. Hessonite is usually cinnamon brown and has been called "cinnamon stone". Hessonite can also be orange; this color is becoming common on the gem markets. Color: Brownish-orange, brownish yellow, aurora red Categories: semi-precious stone Chemical Composition: Ca3Al2(SIO4)3 Crystal Group: Cubic Refractive Index: 1.72-1.74 Hardness: 7.25 Density: 3.65 Occurrence: Sri Lanka, Mexico, Brazil, Canada, Madagascar
| Natural Indicolite Indicolite is a very beautiful stone which is also known as "Blue Tourmaline". It is much different from the other gemstones found in the world.
Indicolite is one of the rarer varieties of elbaite. Color: Blue 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: Brazil, Namibia, U.S.A.
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