| Amorphous | Rocks and mineral without crystal structure |
| Anthracite Coal | Shiny coal |
| Arenaceous | Sediments that have lots of sand |
| Basic rock | Igneous rock with just a little silica content |
| Bedding | Sedimentary rocks with parallel layers |
| Benthonic | On the ocean floor |
| Ciliate | Dusted with small fuzz-like structures |
| Clay | Any soft sediment |
| Cleavage | Minerals that break along smooth surfaces |
| Crystal | Smooth material having a geometric shape and flat sides |
| Drift | Huge pieces of loose materials that cover the earth left behind ice sheets, flooding rivers, and strong wind. |
| Drossy | A drossy in a rock is a hole where well formed crystals form |
| Equigranular | The feel of a rock where the grains are same size |
| Euhedral | Well-formed crystals |
| Extrusive | Rocks from a volcano that have cooled on the surface |
| Extrusive rock | An igneous rock that hardens on the surface of the earth |
| Fragmental rock | Sedimentary rock with mineral fragments |
| Fusion | Being melted or dissolved by heat |
| Hardness | The resistance of a mineral scratching |
| Igneous | A rock that comes out of a volcano on to the earth |
| Intrusion | Where magma wells up, but does not break the land as a volcano does |
| Intrusive rock | Rocks that forms as magma cools - a gradual process |
| Lamellar | Made of delicate and thin flat layers |
| Lava | Molten rock that comes from a volcano on to the surface of the earth |
| Lava flow | A body of rock formed by pouring lava. |
| Luster | The way that the rock or mineral reflects light |
| Magma | The melted rock that builds up in the earth's center |
| Metamorphic Rock | Rocks that have been changed from one structure to another because of great heat and pressure. For instance, limestone becomes marble and granite becomes gneiss. |
| Orogeny | All the ways a mountain range can be made |
| Outcrop | Bedrock that is exposed at the surface of the earth |
| Panicked | A pair of straight crystal faces |
| Petrology | The study of rocks |
| Schillerization | Fantastic color that appear in certain minerals like rode-like inclusions of iron ore |
| Sedimentary rock | Different materials fossilized into a rock from the pressure of the earth's floor |
| Silica | Silicon dioxide that occurs in many forms |
| Sill | Thin layers of igneous rock that is forced in to sedimentary or metamorphic rock |
| Strata | Sedimentary rock that has many layers |
| Streak | The color of the powder of a mineral produced by rubbing the mineral over the surface |
| Structure | It is what a large rock looks like; in minerals it is the shapes and forms of crystals |
| Texture | The surface appearance of a rock |