Granite-gneiss (crushed granite).
Diorite-gneiss (crushed diorite).
Highly foliated gneisses (in which all traces of primitive structure have been obliterated by foliation and recrystallization).
Schists.
Quartz-schists (in some cases probably metamorphosed sandstone, in others crushed aplitic rocks).
Clay-schists (metamorphosed clays).
Hornblende-schists and crushed volcanic rocks.
Hornfels (metamorphosed acid lavas).
Mica-schists (sometimes containing beryl and tourmaline).
Chlorite-schists.