Alexandrite Gemstones Hardness 8.5. Appearance Named after the Russian Czar, Alexander II, alexandrite is the gemstone most noted for it's color changing abilities.
Colors are greenish outdoors, and reddish to violet under artificial light.
Alexandrite is extremely rare. Look out for alexandrite which is too clean, or at a price which seems too low, it's probably synthetic. Natural alexandrite rarely exceeds 2 carats. Can be confused with synthetic alexandrite, or synthetic color change corundum . Pearl, moonstone and alexandrite are the birthstones of the month of June.