Chrysoberyl

A very hard beryllium aluminum oxide. Its varieties include color-changing alexandrite and cat's eye.

Chrysoberyl specimen — Photo: Matteo Chinellato, CC BY-SA 3.0, via Wikimedia Commons

How to identify chrysoberyl

Hardness 8.5 — harder than topaz.
Yellow-green, often in heart-shaped or six-pointed twinned crystals.
Alexandrite looks green in daylight and red under incandescent light.

Often confused with

Olivine
Peridot is much softer and grassier green.
Compare side by side
Beryl
Beryl is softer and forms long hexagonal prisms.
Compare side by side

Where it's found

Sri Lanka
Minas Gerais, Brazil
Ural Mountains, Russia
Tanzania

Uses

Gemstones.

Rock tumbling

Great for tumbling.

Did you know?

Alexandrite was named after Russian Tsar Alexander II.

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