Type of Work in Progress ... A rock that is a mechanical mixture of different minerals and/or rock fragments (clasts). A breccia may also be distinguished by the origin of its clasts: (monomict breccia: monogenetic or monolithologic, and polymict breccia: polygenetic or polylithologic). The proportions of these fragments within the unbrecciated material Click on Term to Read More whose clasts are composed of a single (mono-) rock type, possibly all from a single rock unit (e.g., L6 with L6). Monomict breccias are rare on the Moon because Small rocky or metallic object in orbit around the Sun (or another star). impacts tend to mix different kinds of rocks. The example is a terrestrial An igneous rock consisting mainly of the minerals quartz and alkali feldspar. Click on Term to Read More breccia.
Image Source: http://www.museum.hu-berlin.de/min/zerin/zerin8.jpg