Chrysoberyl

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.

Chrysoberyl is most often a lightly colored gemstone, though increased color saturation will increase its value. Chrysoberyl gemstones are often free of flaws, though stones larger than several carats are uncommon. With a hardness of 8½, Chrysoberyl is also one of the hardest gemstones.

The cat's eye effect exhibited on the Cat's eye variety is caused by is caused by microscopic needle-like fiber inclusions that cause the light to band together in a thin streak. The term "Cat's eye" when used alone without any gemstone name prefix will always refers to Chrysoberyl Cat's eye, which is the most famous and valuable of the cat's eye gemstones. All cat's eye gemstones other than Chrysoberyl must be designated by their gemstone name, such as "Tourmaline Cat's eye", or Cat's Eye Tourmaline.

Source:

The most significant Chrysoberyl deposits are in Brazil, but other important deposits are in Australia, Madagascar, Zimbabwe, Myanmar (Burma), and Russia. Cat's eye is found in Brazil, India, China, Sri Lanka, and Zimbabwe, and Alexandrite comes from Brazil, Russia, Madagascar, Sri Lanka and Tanzania.

Similar Gemstones:

Topaz, Heliodor, Peridot, Yellow Sapphire, Citrine, and Zircon may resemble Chrysoberyl. Chrysoberyl Cat's eye can be distinguished from other cat's eye gemstone by its greater hardness.