|Chemical composition||Al2(BeO4)Beryllium aluminum oxide|
|Optic nature||Biaxial +|
|Refractive index||1.744 - 1.755|
|Specific gravity||3.70 - 3.72|
Alexandrite is a phenomenal variety of the mineral chrysoberyl. Because of the trace amounts of the chromophores vanadium and chromium, alexandrite appears different colors depending on whether it is viewed in natural or incandescent light. In daylight, the stone appears to be green; in artificial light it appears to be raspberry red. It was originally discovered in the Ural Mountains in 1830 on the birthday of Czar Alexander of Russia. Another extraordinary coincidence was that the national colors of Russia were red and green. Today, alexandrite is found in Brazil and to a lesser extent in Africa. Alexandrite has long been associated with great luck and prosperity.
- Cat's Eye
G&G Articles on Alexandrite 1934-1980
- Spring 1949, The Origin of Alexandrite Color Change, p. 143, 3pp.
- Spring 1959, A 45 ct., a 12 ct., and a 50 ct. alexandrite, p. 264, 1p.
- Winter 1963, A cat's-eye alexandrite, p. 104, 2pp.
- Fall 1964, Synthetic alexandrite made, p. 216, 1p.
- Winter 1974, A new synthetic alexandrite by the Czochralski Method, p. 367, 3pp.
- Fall 1976, Alexandrite from Lake Manyara, Tanzania, by Gübelin, p. 203, 11 pp., with bibliography
- Fall 1976, African alexandrites?, p. 211, 3pp.
- Spring 1979, Natural & Synthetic Alexandrites, p. 148, 1p.