Gemstone Chart |
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 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 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 Demantoid The demantoid is one of the most brilliant gemstones that exist, yet until recently it was little known except among collectors and gemstone lovers. Color: Green, yellow green. Categories: semi-precious stone Chemical Composition: Ca3Fe2(SiO4)3 Crystal Group: Cubic Refractive Index: 1.888 - 1.889 Hardness: 6.5 Density: 3.82 - 3.50 Occurrence: Russia, Namibia, Iran, South Africa
| Natural Diamond Diamond is the ultimate gemstone, having few weaknesses and many strengths. It is well known that Diamond is the hardest substance found in nature. Color: White, yellow, brown, black. Rarely, blue, red, or pink. Categories: precious stone Chemical Composition: C Crystal Group: Cubic Refractive Index: 2.417 Hardness: 10 Density: 3.52 Occurrence: Africa, Russia, Canada, Australia, India
| 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
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