| A | B |
|---|
| cleavage | physical property of a mineral that causes it to break along smooth, flat surfaces |
| crystal | a solid having a distinctive shape because its atoms are arranged in repeating patterns |
| fracture | physical property of a mineral that causes it to break with rough or jagged edges |
| gem | a valuable mineral prized for its rarity and beauty |
| hardness | a measure of how easily a mineral can be scratched |
| luster | physical property of a mineral that describes how light is reflected from its surface |
| magma | hot, melted rock material beneath Earth's surface |
| mineral | naturally occurring, inorganic solid with a distinct internal structure & chemical composition |
| ore | a mineral containing a useful substance, such as a metal, that can be mined at a profit |
| silicate | minerals containing silicon and oxygen; the largest group of minerals |
| streak | the color of a mineral when it is powdered; usually observed by rubbing the mineral on a streak plate |
| titanium | durable, lightweight metal obtained from minerals such as ilmenite or rutile |
