Define Greywacke
Greywacke is one of the important type of rocks. If we have to define Greywacke in general, Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay. Greywacke comes under Sedimentary Rocks. All Sedimentary Rocks have similar properties and formation process. Along with Greywacke Definition, know more about the History of Greywacke, Etymology of Greywacke in next sections.