“This chalkopyrite had me puzzled for a while until I found an identical, but broken, crystal revealing the golden metallic color inside. The black coating ( possibly tenorite) is perhaps 0.5mm thick and of uniform thickness. ”

“This chalkopyrite had me puzzled for a while until I found an identical, but broken, crystal revealing the golden metallic color inside. The black coating ( possibly tenorite) is perhaps 0.5mm thick and of uniform thickness. ”