Rocksday

Augite

The most common pyroxene, forming stubby black crystals in basalt and gabbro.

Augite specimen
Photo: Didier Descouens, CC BY-SA 4.0, via Wikimedia Commons

How to identify augite

  • Short, stubby black prisms with an eight-sided cross-section.
  • Two cleavages at nearly right angles.
  • Found in dark volcanic rocks.

Often confused with

Where it's found

  • Basalts worldwide
  • Mount Vesuvius, Italy
  • Bohemia, Czech Republic

Uses

A major component of basalt and gabbro.

Rock tumbling

Can be tumbled with care.

Did you know?

Volcanic ash from Stromboli and Etna often contains loose augite crystals.

Think you could spot it from a blurry close-up?

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