Rocks come in many shapes, textures and colours.
But they are all formed in one of three ways. Some is spewed out by volcanoes to form extrusive igneous rock. Some is forced up beneath the surface, forming intrusive igneous rock. Molten magma is incredibly hot as it nears the surface, but it soon starts to cool. As it cools, more and more crystals appear, until eventually all the magma becomes a solid mass of hard, crystalline rock.