| A | B |
|---|
| Basalt | Dark-colored, dense igneous rock that forms from magma rich in iron and magnesium. |
| Cementation | Sedimentary rock-forming process in whihc large sediments are glued together by minerals deposited between sediments. |
| Compaction | Sedimentary rock-forming process that occurs when layers of small sediments become compressed by the weight of layers above them. |
| Extrusive | Igneous rocks that form when magma cools on the Earth's surface. |
| Foliated | Metamorphic rock created when mineral grains flatten and line up in parallel bands. |
| Granite | Light colored igneous rock formed from magma rich in silicon and oxygen. |
| Igneous Rock | Rock formed by the cooling and melting of molten material from a volcano. |
| Intrusive | Igneous rocks formed when magma cools below Earth's surface; generally have large mineral grains. |
| Lava | Molten rock from a volcano flowing onto Earth's surface. |
| Metamorphic Rock | Rock formed from sedimentary, igneous, or other metamorphic rock due to increases in heat and pressure. |
| Nonfoliated | Metamorphic rock created when mineral grains change, grow, and rearrange, but do not form bands. |
| Rock | Earth material made of a mixture of one or more minerals, glass, mineraloids, or organic matter. |
| Rock Cycle | Process by which, over many years, Earth materials form and change back and forth among igneous rocks, sedimentary rocks and metamorphic rocks. |
| Sediment | Loose materials such as rock fragments, mineral grains, and bits of plants and animals that have been transported by wind, water, or glaciers. |
| Sedimentary Rock | Rock formed when fragments of rocks, minerals, and/or organic matter are compacted or cemented together or precipitate out of solution. |
| Cleavage | Physical property of a mineral that causes it to break along smooth, flat surfaces. |
| Crystal | 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. |
| Hardness | A measure of how easily a mineral can be scratched. |
| Luster | The physical property of a mineral that describes how light is reflected from its surface; is defined as either metallic or nonmetallic. |
| Magma | Hot, melted rock material beneath Earth's surface. |
| Ore | A mineral containing a useful substance, such as a metal, that can be mined at a profit. |
| Silicate | Minerals containing silicon and oxygen, usually with other elements; the largest group minerals. |
| Streak | Color of a mineral when it is powdered; usually observed by rubbing the mineral on a ceramic streak plate. |
| Mineral | Naturally occurring, inorganic solid with a distinct internal structure and chemical composition. |
