The Igneous Rock Granite

Graniteis a type of igneous rock that consists of quartz gray plagioclase feldspar white and alkali feldspar beige plus dark minerals such as biotite and hornblende.

The igneous rock granite. Granite is an intrusive igneous rock. If magma cools slowly deep within the crust the resulting rock is called intrusive or plutonic. Intrusive rocks form from molten material magma that flows and solidifies underground where magma cools slowly. Igneous rocks from the greek word for fire form when hot molten rock magma crystallizes and solidifies.

It is the most common plutonic rock of the earth s crust forming by the cooling of magma silicate melt at depth. Magma that rises to the surface is called lava. Photo by eva didonato. Granite is used by the public as a catchall name for any light colored coarse grained igneous rock.

Granite is composed mainly of quartz and feldspar with minor amounts of mica amphiboles and other minerals. Granite coarse or medium grained intrusive igneous rock that is rich in quartz and feldspar. Perhaps the best known phaneritic rock is granite. Granite is the most widespread of igneous rocks underlying much of the continental crust.

The black colors are likely two or three different minerals. Granite is a classic coarse grained phaneritic intrusive igneous rock. Devil s tower national monument in wyoming is an example of an igneous rock. The different colors are unique minerals.

One extreme type of phaneritic rock is called pegmatite found often in the u s. Magma originates deep within the earth near active plate boundaries or hot spots. Granite is a light colored igneous rock with grains large enough to be visible with the unaided eye. Eventually the overlying rocks are removed exposing the granite.