| A | B |
|---|
| rock | a naturally-formed solid made of one or more minerals |
| mineral | a solid, naturally occurring, crystalline object witha defined chemical composition |
| cleavage plane | a surface along which a mineral cleanly splits |
| Mohs hardness scale | a scale to identify minerals based on their hardness or resistance to being scratched |
| rock cycle | the formation and recycling of rocks by geologic processes |
| igneous rock | a rock formed from the cooling and crystallizing of magma or lava |
| sedimentary rock | a rock made of sediments that are cemented together by pressure and chemical changes |
| sediment | small rock particles, minerals, and bits of once-living things |
| metamorphic rock | a rock formed from another rock because of heat and pressure |
| crystallization | the process by which crystals form and grow in size |
| basalt | a dark-colored igneous rock with fine crystals. Formed from lava that is not silica-rich. This rock forms oceanic crust. |
| granite | an igneous rock with large, visible crystals. Formed from silica-rich magma. This rock forms continental crust. |
| extrusive rock | an igneous rock that cools outside of Earth's crust. |
| intrusive rock | an igneous rock that cools inside Earth's crust. |
| compaction | the process by which sediment is pressed together as more and more layers or beds of sediment form on top of each other. |
| cementation | the process by which sediment particles are "glued" together to make a sedimentary rock. |
