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Chrysoberyl:
Multiple Oxides (Beryllium aluminum oxide, often with small amounts of iron and chromium) BeAl2O4 AKA: Alexandrite, Cat's eye, Precious Cat's eye |
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System: Orthorhombic; usually tabular or primatic crystals; also disseminated plates; forms heart-shaped or pseudohexagonal twins. Appearance: Yellowish green, deep green, greenish white, greenish brown, yellow; vitreous, streak white. Physical properties: Hardness: (8.5), Specific gravity: (3.5 - 3.8), Cleavage: Good in one direction, poor in two others; fracture conchoidal, uneven; transparent to translucent; brittle. Similar species: Chrysoberyl is harder and heavier than beryl, with which it is usually associated. Occurrence: Chrysoberyl occurs with beryl, microcline and tourmaline in granite pegmatites, and with albite and almandite in schist of regional metamorphic rocks. The finest alexandrite comes from near the Ural Mountains in the former USSR. Most gem-quality chrysoberyl comes from Brazil, Ceylon, China, Rhodesia and Russia. Miscellaneous: Dark yellow-green to slightly bluish-green that appears red under artificial light is called alexandrite. All other colors are known simply as chrysoberyl. Some pale yellow to dark bluish-green stones exhibit a floating billowy light, which moves when the stone is rotated, this effect is called cymophane, and is caused by microscopic rutile inclusions. When the cymophane is restricted to a narrow band, precious Cats eye or chrysoberyl Cat's eye is produced. Alexandrite and chrysoberyl are faceted, whereas Cat's eye must be fashioned as cabochons. Conventional Wisdom: It is a "stone of immortality", assisting one to both overcome and progress toward excellence. It elevates ones sense of self-worth and helps one to understand and to actualize the intrinsic state of perfection which is available. It is also said that it causes one to be more charitable toward their neighbor. Belongs to the Astrological Sign of Leo. |