Metamorphic rock
Migmatite
A mix of metamorphic and igneous rock formed when a rock is heated to partial melting: felsic minerals (feldspar, quartz) melt while mafic minerals (biotite, hornblende) remain. Ptygmatic folds are common.

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Other metamorphic rocks
Slate · Phyllite · Schist · Gneiss · Amphibolite · Marble · Quartzite · Hornfels
Sources
Panchuk, Physical Geology 10.3: Classification of Metamorphic Rocks