Rocks

Rocks come in many colors. What causes the different colors of rocks?

• The minerals, impurities, and chemical composition in the rock

• The temperature of the rock

• The size of the rock particles

• The age of the rock

What is the definition of a mineral?

• A substance that is only man-made

• A naturally occurring, inorganic solid with a definite chemical composition and an orderly arrangement of atoms

• A substance that is always liquid at room temperature

• A rock made of organic materials

What is the difference between coarse-grained, medium-grained, and fine-grained rocks?

• Coarse-grained rocks have larger mineral grains, medium-grained rocks have medium-sized grains, and fine-grained rocks have smaller grains.

• Coarse-grained rocks have smaller grains than medium-grained rocks.

• Fine-grained rocks are made of large crystals, while coarse-grained rocks are made of tiny particles.

• All rocks are fine-grained.

Minerals are always organic substances.

• True

• False

The way light interacts with the surface of a mineral is called its __________.

• luster

• hardness

• density

• cleavage