Gneiss goes through metamorphosis at a higher temperature than slate so it has a higher

Grade of metamorphism

Explanation:

Gneiss forms at a higher grade of metamophic slate. Slate forms at low metamorphic conditions just about a few temperature and pressure.

From the prolith materials exposed to metamorphic conditions, transformations begins as metamorphic changes begins to take place. First, a sediment is transformed into slate, from slate to phyllite, from phyllite to schist, schist to gneiss, gneiss to migmatite and migmatite goes back to melt. These transformation of sediments is controlled by the nature of the prolith materials and the prevailing metamorphic conditions.

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