Composition: Beryllium aluminum oxide
Nomenclature: Named after the Greek words chrysos and beryllos which mean "golden" and "a green stone," respectively.
Industrial Uses: Gemstones; beryllium ore.
Additional Notes: Frequently occurs in hexagonal, cyclic twinned crystals. The cat's eye variety of chrysoberyl displays a movable band of reflected light similar to the reflection of light from a roll of silk cloth. Alexandrite is a variety of chrysoberyl that appears green in sunlight and brownish-violet in incandescent light.
Comoro Islands : Scott 930f : 375 francs : 1998
Chrysoberyl
Sri Lanka : Scott 508 : 1.15 rupees : 16 Jun 1976
Chrysoberyl (cat's eye)