An impressive, stout, brilliant metallic crystal of cogwheel bournonite from the famed Yaogangxian polymetallic deposit in China. This exceptional large, single crystal exhibits striated prism faces along with pinacoid and pyramid faces that display subtle growth hillocks adding to the reflectivity. Minor edge rubbing locally and patchy less reflective areas on the backside that are inconsequential to this great piece. Ex. Paul Zerfass collection with label. Classic and fine robust, lustrous piece from the early 2000's.