So, foliation of phyllites is different from the foliation in slates that stems from clay mineral alignment, and various from foliation in schists for the reason that schists constantly contain noticeable mica grains. Like slates, phyllites exhibit fissility. Many mantle xenoliths, carried up as nodules in magma, are eclogites. Eclogites https://www.generationgenius.com/videolessons/rocks-and-minerals-video-for-kids/