Breccia

Sharp, broken rock fragments cemented together. It forms where rock shatters — at faults, landslides or impacts.

Breccia specimen — Photo: No machine-readable author provided. Siim assumed (based on copyright claims)., CC BY-SA 3.0, via Wikimedia Commons

How to identify breccia

Angular, broken fragments.
Fragments set in a finer matrix.
Fragments often of one rock type.
Looks like a smashed and glued mosaic.

Often confused with

Conglomerate
Conglomerate's pebbles are rounded.
Compare side by side

Where it's found

Fault zones worldwide
Sudbury, Ontario
Tuscany, Italy (decorative breccias)

Uses

Decorative stone and countertops.

Rock tumbling

Can be tumbled with care.

Did you know?

Meteorite impacts create breccia — Ontario's Sudbury Basin is full of it.

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

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