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Rocks disrobe throughout metamorphism because the metals require to be durable under the new temperature and confinement requirements. The demand for stability may create the composition of metals to reorganize and create new minerals. Ions may move among metals to produce minerals of various chemical combination. . The kind of rock that a metamorphic stone used to be, before metamorphism, is described the protolith which requires to be older. During metamorphism the metal content and composition of the protolith are modified due to variations in the mechanical and chemical conditions of the rock. Metamorphism can be created by burial, tectonic stress, warming by magma, or modification by fluids.