NAME | CHARACTERISTICS | ORIGIN |
Slate | Strongly aligned, not necessarily along bedding | Sedimentary shale and clay |
Phyllite | Coarser than slate; sometimes folded | Medium-grained sediments |
Schist | Contains mica (glittery flakes) | Siltstones and other deeply-buried sediments |
Gneiss | Medium/coarse - quatrz, fledspar, mica Granite or sediments under very high pressure and temperature | deep underground |
Migmatite | Strongly folded - schist, granite | Sediments |
Eclogite | Coarse-grained - pyroxene and garnet Formed under very high pressure and temperature | close to surface |
Amphibolite | Coarse-grained, foliated - mostly hornblende | Igneous dolerite |
Marble | Crystalline, soft - calcium carbonate | Limestone |
Hornfels | Fine-grained - dark colour; quartz, mica, pyroxene | Sediments close to igneous intrusion |
Quartzite | Medium-grained, even textured ; very hard | Sandy sediments |
Serpentenite | Coarse-grained - green serpentine | Olivine-rich rocks |
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