Rocks and Minerals
You need minerals to make rocks, but you don't need rocks to make minerals.
All rocks are made of minerals.
Rocks are constantly being formed, worn down and then formed again.
This is known as the Rock Cycle.
Rocks are divided into three types:
All rocks on Earth were initially igneous in nature. Igneous rocks form as liquid magma cools, forming crystal structured rocks.
Sedimentary rocks are called secondary, because they are often the result of the accumulation of small pieces broken off of pre-existing rocks