Rock Types:
A rock is a record of the environment in which it formed

Rocks:

What is a rock? A purely descriptive definition is that a rock is - A naturally occurring aggregate of minerals and other solid material. - Usually, there are several minerals in the aggregate, though some rocks may have only one. The other materials may include natural glasses, organic material, or fossils.

Geologists usually think of rocks in a second important way, however. Please memorize this and recite it like a mantra:

* A rock is a record of the environment in which it formed. *

Rock types: