| NAME | CHARACTERISTICS | ORIGIN |
| Granite | Coarse - acid | Intrusive batholiths |
| Pegmatite | Coarse - acid - very large crystals | Deep batholiths and dykes |
| Diorite | Coarse - intermediate | Dykes associated with granite |
| Syenite | Coarse - intermediate - often pink | Dykes and sills near granite |
| Gabbro | Coarse - basic | Large intrusions |
| Larvikite | Coarse - intermediate | Small sills |
| Anorthosite | Coarse - basic - aligned grains | Layered intrusions; also found on the moon |
| Dolerite | Medium - basic - dark in colour | Dykes and sills near basalt |
| Dunite | Medium - ultrabasic | Intrusions from great depth |
| Kimberlite | Coarse - ultrabasic - sometimes diamond-bearing | Pipes of ancient volcanoes deep underground |
| Peridotite | Coarse - ultrabasic | Intrusions |
| Rhyolite | Fine - acid | Explosive volcanic eruptions |
| Obsidian | Glassy - acid - black, occasionally with "snowflakes" | Acid lava subjected to rapid cooling |
| Lamprophyre | Medium - acid/basic | Dykes and sills near granite |
| Andesite | Fine - intermediate - dark in colour | Volcanic eruptions |
| Trachyte | Fine - intermediate | Lava flows, dykes and sills |
| Basalt | Fine - basic - dark in colour | Volcanic eruptions - the commonest lava |
| Tuff | Fine - acid/basic | Volcanic vents |
| Pumice | Fine - acid/basic - sometimes can float on water | Frothy lava cooled rapidly |
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