cabochon from polished jaspillite gem

background banded brown close closeup collage collection colorful cut cutout ferruginous gemstone geological geology hematite iron isolated itabirite jasper jaspilite jaspillite layered lmany macro metamorphic mineral natural ore out pebble piece polished quartzite raw red rock rolled rough sample set specimen stone structure surface taconite texture textured tumbled unpolished various white