Pearl

A gem grown inside a mollusk from layers of nacre — aragonite and protein.

Pearl specimen — Photo: MASAYUKI KATO, CC BY-SA 3.0, via Wikimedia Commons

How to identify pearl

Deep glow (orient) from overlapping nacre layers.
Feels gritty when rubbed gently against teeth; imitations feel smooth.
Cool to the touch at first.

Often confused with

Aragonite
Pearl nacre is aragonite, but ordinary aragonite has no layered glow.
Compare side by side

Where it's found

Persian Gulf
Japan (Akoya)
French Polynesia (Tahitian)
Australia (South Sea)

Uses

Jewelry.

Rock tumbling

Not suitable for tumbling.

Did you know?

Kokichi Mikimoto produced the first cultured round pearls in Japan in the early 1900s.

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