The rock that consists of quartz, feldspar, and mica crystals is called granite. Granite is a common type of igneous rock that is formed from the slow cooling and solidification of magma or lava deep within the Earth's crust. It is typically composed of quartz, feldspar, and mica minerals, but may also contain other minerals such as hornblende, biotite, and muscovite. Granite is known for its durability, hardness, and resistance to weathering, which makes it a popular material for building and construction, including countertops, flooring, and monuments. It is also used as a decorative stone in landscaping and outdoor projects.