(2) Schist-Gneiss Explanation: The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Gneissic rocks are usually medium- to coarse-foliated and largely recrystallized but do not carry large quantities of micas, chlorite or other platy minerals. Mica minerals make some rocks sparkle! They are often found in igneous rocks such as granite and metamorphic rocks such as schist. Most schists are mica schists, but graphite and chlorite schists are also common. Schist is a crystalline metamorphic rock, mostly composed of more than 50% tabular and elongated minerals.