Definition: Alexandrite is a transparent gemstone that was discovered in Russia in 1831. Its name honors Czar Alexander II of Russia.
Alexandrite shifts color, appearing green or bluish-green in sunlight and red or reddish-brown in incandescent lighting.
A member of the chrysoberyl family of gems, Alexandrite is somewhat rare, especially as a large stone. It is rated at a hardness of 8.5 on the Mohs scale.
Not all gemstones marketed as alexandrite are true alexandrite. Some are other members of the chrysoberyl family that change color less dramatically.
