Chrysoberyl (pronounced KRIS-dh-barrel), which is derived from two Greek words meaning "golden" and "Beryl", is one of the most interesting, yet least known, of the important gems. Probably the best-known variety is the cat's-eye. With its silky luster and sharp "eye", it is the most beautiful chatoyant stone known in nature. In the Orient, cat's-eye is highly revered as a preserver of good fortune, the belief being that it guards the owner's health and protects him from poverty.
Alexandrite is particularly interesting because of its color change; the more poetic writers have referred to it as "an emerald by day and a ruby by night". This variety received its name from the fact that it was supposedly discovered on the birthday of Alexander II, Czar of Russia, in 1830. Because of this, and because red and green are the colors of the Russian Imperial Guard, alexandrite has been a particular favorite in that country.