Granite general, descriptive field term for lighter-colored, coarse-grained igneous rocks. Petrographic examination is required for identification of specific types of granitoids. The extrusive igneous rock equivalent of granite is rhyolite. Granite is nearly always massive (i.e., lacking any internal structures), hard, and tough. These properties have made granite a widespread construction stone throughout human history. The average density of granite is between , its compressive strength usually lies above 200 MPa, and its viscosity near STP is 3–6·10 Pa·s. The melting temperature of dry granite at ambient pressure is ; it is strongly reduced in the presence of water, down to
Exfoliating granite a couple hundred feet thick, separates from the underlying granite along an expansion joint to form a shell. As this continues, several concentric shells may form to depths of feet or more. Concentric slabs/shells of rock begin to break loose, onion-like layers subparallel to the exterior called exfoliating, sheet jointing, or fractures. As the granite expands the outer, most shells become susceptible to weathering by water pressure, freeze/thaw cycles, and functioning vegetation is a process called physical weathering. The sheets of granite are large enough to shave off sharp edges on the granite’s surface creating a dome shape. The overall