Chrysoberyl is a hard, tough, and durable gem. Although lacking the fire of other gemstones, Chrysoberyl in its various forms can be quite valuable. Most Chrysoberyl gems are yellow, though some are brown, green, or orange. Chrysoberyl is best known for its important varieties Alexandrite and Cat"s Eye. Alexandrite is a rare and expensive form that exhibits different colors in natural and artificial light. Cat"s Eye is Chrysoberyl that is polished into a cabochon and highly chatoyant, displaying a sharp line of light through the center of the stone.
Chemical Formula | BeAl2O4 |
Color | Red, Green, Yellow, Orange, Brown, Pink, Gray, Black, Multicolored |
Hardness | 8.5 |
Crystal System | Orthorhombic |
Refractive Index | 1.744Â -Â 1.755 |
SG | 3.5Â -Â 3.8 |
Transparency | Transparent to translucent |
Double Refraction | .009 |
Luster | Vitreous |
Cleavage | 1,1 ; 3,2. Often exhibits parting along twinned crystals. |
Mineral Class | Chrysoberyl |
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