Minerals and Rocks

The surface of the earth is covered by a layer of rock.

It's called the Earth's crust.

Rocks are made up of grains of

different materials-minerals.

In some rocks, the minerals form

small crystals.

Granite is a rock made from large

crystals of three different minerals

( quartz, feldspar, and mica ).

Igneous rock is

formed through the

cooling and

solidification of

magma or lava.

They are formed on

or near the Earth’s

surface from the

compression of

ocean sediments or

other processes.

Metamorphic rocks started

out as some other type of

rock, but have been

substantially changed from

their

original igneous, sediment

ary, or earlier

metamorphic form.