| A | B |
|---|
| Element | A substance that cannot be broken down into a simpler substance by ordinary chemical changes. |
| Mineral | A substance that forms in nature, is a solid, has a definite chemical makeup, and has a crystal structure. |
| Crystal | A solid substance in which the atoms are arranged in an orderly, repeating, three-dimensional pattern. |
| Density | A measure of the amount of matter packed into a unit volume |
| Streak | The color of a mineral powder left behind when a mineral is scraped across a surface; a method for classifying minerals. |
| Luster | The property of a mineral that describes the way in which light reflects from its surface. |
| Cleavage | The property of a mineral that describes its tendency to break along flat surfaces. |
| Fracture | The tendency of a mineral to break into irregular pieces. |
| Hardness | The resistance of a mineral or other material to being scratched. |
| Magma | Molten rock beneath Earth’s surface. |
| Lava | Molten rock that reaches a planet’s surface through a volcano |
| Ore | A rock that contains enough of a valuable mineral to be mined for a profit. |
