The 3 Types of Rock
Igneous rocks are the oldest type of rock. They generally begin as a hot, fluid material. This material could be lava or magma. Basalt, Granite and Pumice are all igneous rocks.
Sedimentary rocks are formed from mud or sand. Sandstone, shale and conglomarate are all examples of sedimentary rocks.
Metamorphic rocks are transformed from already existing rocks. Slate, quartz and marble are all examples of metamorphic rocks.