What is Granite? Granite is normally a coarse grained igneous rock that is comprised of quartz, feldspars and micas. The quartz will be the lighter color minerals with the remaining consisting go feldspars and muscovite. The dark minerals are hornblende or biotite. Granite is by far the most common rock found in the outer crust of the planet, formed by the cooling of magma in the ground. Granite is an excellent material for counters due to its hardness and ability to resist stains.