There are over 5,000 known types of minerals ... combinations of these minerals are endless. Rocks also differ based on how they were formed. Igneous rocks form out of cooling lava or magma.

Igneous rocks close igneous rockIgneous rocks are those which have been formed by the cooling and solidification of molten rock (magma) from underneath the earth’s crust. are formed by magma ...

There are three types of rock: igneous ... producing extrusive or volcanic igneous rocks like basalt. As magma cools, the minerals within it begin to crystallize and interlock to create solid ...