volcanic breccia

Breccia (IPA: , ) is a rock composed of angular fragments of rocks or minerals in a matrix, that is a cementing material, that may be similar or different in composition to the fragments. A breccia may have a variety of different origins, as indicated by the named types including sedimentary breccia, tectonic breccia, igneous breccia, impact breccia and hydrothermal breccia.
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