Alexandrite is a green or blue gem that turns red or purple under incandescent light. The largest alexandrites are measured in the tens of carats, albeit even stones approaching five carats are rather rare. The stone is named for Czar Alexander II of Russia, as it was discovered on his 21st birthday and was a favorite gemstone of the Russian aristocrats. Alexandrite is considered a good luck amulet.
The stone may be artificially simulated by a color-changing synthesized sapphire (corundum). This material is sometimes called “alexandrine” and is not used by reputable dealers.
When purchasing alexandrite, pay special attention to the clarity of the two featured colors and to the completeness of the color change.
The more intense the color and the more dramatically the gem shifts from one color to the other (without any brown bleeding over during the change), the more valuable the gem.
Protect alexandrite from scratches, sharp blows, harsh chemicals, and extreme temperatures. Be especially careful when (re)mounting this stone, as the heat from a jeweler’s torch may alter its color.
