Moonstone

A feldspar made of microscopic alternating layers that scatter light into a soft, floating blue-white glow called adularescence.

Moonstone specimen — Photo: Didier Descouens, CC BY-SA 3.0, via Wikimedia Commons

How to identify moonstone

A milky glow that seems to float just under the surface.
The glow moves as you tilt the stone.
Flat cleavage faces on rough pieces; hardness about 6.

Often confused with

Labradorite
Labradorite is darker with vivid blue, green or gold flashes; 'rainbow moonstone' is actually white labradorite.
Compare side by side
Opal
Opal shows patches of spectral colors rather than one floating sheen.
Compare side by side

Where it's found

Sri Lanka
India
Myanmar
Madagascar

Uses

Cabochons and beads.

Rock tumbling

Can be tumbled with care. Cleaves easily; tumble gently.

Did you know?

Florida made moonstone its state gem in 1970 to honor the Moon landings — though it isn't found there.

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