Breccia (/ˈbrɛtʃiə, ˈbrɛʃ-/) is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix.
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Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down.