So, foliation of phyllites differs from the foliation in slates that stems from clay mineral alignment, and unique from foliation in schists for the reason that schists normally consist of seen mica grains. Like slates, phyllites exhibit fissility. Exceptionally widespread inside the Earth's crust, igneous rocks are volcanic and type https://www.generationgenius.com/videolessons/rocks-and-minerals-video-for-kids/