Phyllite thin section microscope slide exhibiting textbook crenulated cleavage and occasional garnets ideal for those who want to practice the recognition of metamorphic textures & features in thin section. Phyllite is a type of foliated metamorphic rock created from a slate or pelite protolith that has further metamorphosed so that very fine grained white mica achieves a preferred orientation. It is primarily composed of quartz, sericite mica, and chlorite. Sometimes minute crystals of graphite, sericite, or chlorite, or the translucent fine-grained white mica, impart a silky, sometimes golden sheen to the surfaces of cleavage, called "phyllitic luster". This material was collected from Kinlochleven in Scotland. The glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy, petrography & educational use.