Intrusive igneous rocks.... from below the surface!
Intrusive igneous rocks are rocks formed when magma hardens beneath Earth's surface. The magama cools over thousands to millions of years until it completely forms intrusive rocks. The most abundant intrusive igneous rock found on Earth is GRANITE. Lots of intrusive rocks are used for everyday uses. Granite has been used for thousands of years to build statues and memorials. Granite countertops are widely used, and granite floors are also made. The crystals in an intrusive rock are large and easy to see, so to observe them- you don't need a microscope. You can remember the word INTRUSIVE, because IN- is inside the Earth.