set of various rough black stones with name cutout

amphibole amphibolite amphibolithe argillite background biotite bituminous black bornite claystone coal collage collection cut cutout description dunite flint gabbro gray hematite ilmenite iron isolated knopite mica mineral mudstone name natural nepheline olivinite ore out peacock quartz raw rock rough sample schist schorl set shale shungite specimen stone syenite tourmaline unpolished various white