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
Bohus granite Bohus granite The Bohus granite () is a type of granite that crops out along the Swedish West Coast in Bohuslän. In Norway the same granites are termed Iddefjord granite (), Østfold granite and Halden granite. A large quarrying industry has developed around the granites, mainly producing blocks. Large scale extraction begun in the 1840s and employment in the quarries peaked in the 1920s with over 7,000 people working in the industry. The rock is valued for its durability. In the first half of the 20th century the transport of quarried Bohus granite was done with the aid of by