Thumbnails can be downloaded. The Story of Igneous Rock Igneous rock is formed when molten magma from deep within the earth cools and finally freezes into solid form. If the rock has cooled slowly below the surface, individual crystals will grow larger before intersecting, and coarse grained plutonic rocks such as granite are formed. This site contains a multiple-choice quiz on igneous rocks. Its is suited to high school level students.
Igneous rocks form from magma crystallizing below earth's surface or from volcanic activity.
Igneous rocks are classified on their texture and their composition. Granite Granite is one of the most common rocks on our planet. It is an igneous rock that was formed from hot, melted rock called magma. The hot, liquid rock is called magma while it remains underground and is called lava when it comes out of the earth's crust during a volcanic eruption. Basalt Basalt is another example of an igneous rock.