Dioptase

An intensely emerald-green copper silicate that forms glittering short crystals.

Dioptase specimen — Photo: Géry PARENT, CC BY-SA 4.0, via Wikimedia Commons

How to identify dioptase

Vivid emerald green, often a sparkling crystal crust.
Short six-sided crystals with rhombic tips.
Hardness 5 — a knife scratches it.

Often confused with

Emerald
Emerald is harder and forms longer prisms.
Compare side by side
Uvarovite
Uvarovite crystals are tiny, round and harder.
Compare side by side

Where it's found

Tsumeb, Namibia
Altyn-Tyube, Kazakhstan
Katanga, DR Congo

Uses

Collector specimens.

Rock tumbling

Not suitable for tumbling.

Did you know?

Miners in 18th-century Kazakhstan sold dioptase as emerald.

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