Apophyllite

A sparkling silicate from cavities in basalt, forming blocky square crystals with pyramid tips.

Apophyllite specimen — Photo: Robert M. Lavinsky, CC BY-SA 3.0, via Wikimedia Commons

How to identify apophyllite

Clear or mint-green square prisms or pyramids.
Pearly shine on the flat top faces.
Softer than quartz — a knife scratches it.

Often confused with

Quartz
Quartz is harder and its crystals are hexagonal.
Compare side by side
Calcite
Calcite fizzes and cleaves into rhombs.
Compare side by side

Where it's found

Pune, India
Nashik, India
Nova Scotia
Iceland

Uses

Collector specimens.

Rock tumbling

Not suitable for tumbling.

Did you know?

The name means 'to flake off' — it flakes apart when heated.

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