Marble forms from limestone by metamorphic recrystallization. The mechanical break-up or disintegration of rock into smaller fragments. . Mixture of rocks formed by tectonic disruption, such as multiple faulting , which brings disparate rock types together. Usually consists of a matrix of weak material, like shale , with hard pieces of exotic rocks, such as gneiss or igneous rocks. A rock that has undergone chemical or structural changes produced by increase in heat or pressure, or by replacement of elements by hot, chemically active fluids.
All micas form flat, plate-like crystals.
Crystals cleave into smooth flakes. In geology, a mound of organic debris or organic-rich soil created by an animal. In archeology, a mound of human refuse. A metamorphic rock that forms in one of two ways. The metamorphic rock may be heated enough to partially melt, but not completely.