Metamorphic rocks are classified as being
foliated or being
non-foliated. Foliated metamorphic rocks have visible banding or sheet-like layering. Slate, phyllite, gneiss, and schist are foliated metamorphic rocks. Non-foliated metamorphic rocks do not display banding or layering. Marble and quartzite are non-foliated metamorphic rocks.
Metamorphic rocks can also be classified as either regional metamorphic rocks or contact metamorphic rocks, depending on their method of formation.