Streak is a mineral property. It is the color of the powder left behind when you rub a mineral against a white tile.

Luster is a mineral property. It describes the way the surface of a mineral reflects light.

Hardness is a mineral property. It is a mineral’s ability to resist being scratched.

We use minerals to make jewelry, coins, metal objects, plaster, and wires.

There are 3 types of rocks (igneous, sedimentary, and metamorphic).

Igneous rocks form when melted rock hardens.

Sedimentary rocks form over a long period of time by layers of sediments being squeezed and stuck together.

Metamorphic rocks form when a rock is put under great heat and pressure.

Rocks can change over time. Weathering can slowly break a rock into pieces.

In the rock cycle, rocks change from one kind of to another.