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
Dedham Granite Dedham Granite Dedham Granite is a light grayish-pink to greenish-gray, equigranular to slightly porphyritic, variably altered, granite south and west of Boston, named for the town of Dedham, Massachusetts. Dedham Granite includes dioritic rock near Scituate and Cohasset and Barefoot Hills Quartz Monzonite. Intrudes Zdi, Zgb, Zb, Zv. Extensive calc-alkaline plutons separated by Boston basin have long been mapped as Dedham. Those to the north of Boston and studied by the US Geological Survey, are referred to as Dedham North. Crystallization ages for the Dedham North suite (based on titanites and zircons) have been determined at 607+/-4 Ma, while ages