Schist is a metamorphic rock that displays a foliated (folded) texture as a result of intense pressure that causes alignment of platy minerals. Metamorphism, intense heat and pressure, causes the rearranging or recrystallization of components in a rock, to create a new rock with new minerals. Impure limestones can be transformed by metamorphism in this way; actinolite schist, a rock made up almost entirely of the mineral actinolite, is one possible result.