For ten points, name this course-grained rock produced by regional metamorphism.
This type of rock is distinguished by its high tendency to split into layers and its poorly developed foliation. Mostly composed of platy minerals, such as muscovite, talc, and graphite, it is formed under higher pressure than slate and is differentiated from gneiss, which has a poor tendency toward cleavage and well-developed foliation. For ten points, name this course-grained rock produced by regional metamorphism.
This type of rock is distinguished by its high tendency to split into layers and its poorly developed foliation.
schist