Igneous rocks is a type of rock made from magma. After a volcano erupts and the magma dries, an igneous rock is formed. There is two types of igneous rocks: Intrusive and Extrusive In this section you will learn about both types.
Intrusive Igneous Rocks
The Reason why not all igneous rocks look the same is because they do not form the same way. Intrusive igneous rocks is only one of the two ways and igneous rock is formed. The first type being intrusive igneous rocks and the second being Extrusive. Intrusive Igneous Rocks form deep inside the earth from cooling magma. These rocks form very slowly but grow very large crystals.
Extrusive Igneous Rocks
Extrusive Igneous Rocks are found, unlike Intrusive Igneous Rocks, on the surface and is formed from fast cooling lava. While the rest of the igneous rocks are formed by magma, Extrusive Rocks are not. These types of rocks form little crystals if any. Rhyolite is and example of a Extrusive Igneous Rock.