They are relatively common sedimentary clastic rocks formed in situations of great violence, where the original rocks break and regroup near the impact site. Breccias composed of several minerals, such as calcite, quartz (silica), clay and plaster. Because they normally have significant porosity and they act in nature as a reservoir of groundwater, natural gas and oil. It is a stone with unique angular texture and famous for its use in buildings, monuments, tombs, tiles and others. It has been used for centuries for many ornamental uses and some are still considered to be semi-precious stones and used for jewelry making.