phyllite formed under which metamorphic conditions
Phyllite is formed by relatively low-grade metamorphic conditions in the lower part of the greenschist facies. Parent rocks may be only partially metamorphosed so that the original mineralogy and sedimentary bedding are partially preserved.HYLLITE. Phyllite is a fine-grained metamorphic rock formed by the low grade metamorphism of fine-grained, sedimentary rocks, such as mudstones or shales.