Breccia
A breccia is a rock made of broken, angular fragments of older rocks stuck together into a new rock.
The word breccia (say "BRECH-ee-a") comes from Italian and refers to rubble. Geologists use it for any rock built from angular broken pieces cemented or welded together. On asteroids and moons, the main rock-breaker is impact: collisions smash the surface, mix the debris and press or melt it back into solid rock.
Breccias are extremely common among meteorites, because asteroids have been bombarded for over four billion years. Scientists sort them into types. A monomict breccia contains fragments of just one kind of rock, a polymict breccia mixes different kinds, and a regolith breccia formed from the loose, sun-exposed soil on an asteroid's surface. Howardites, after which this site is named, are polymict breccias from the asteroid Vesta, mixing pieces of eucrite and diogenite. Kapoeta, a howardite that fell in South Sudan in 1942, is a famous example.
To recognise a breccia, look at a cut face for a patchwork of angular pieces in different colours or textures, set in finer material. Some meteorite breccias look like a stone mosaic. Leave cutting and polishing to adults with proper equipment.
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Level: Explorer Ages 10 and up