Extremely rare, this is a copper sulfide seldom found in such richness. I have never even SEEN one. I got this from a friend I trust in such matters, Gunnar Farber, and he assured me by both his own pricing and a few exclamatory points on the label, that it is absolutely outstanding for the species. These are 3-dimensional crystals, partially embedded I nthe matrix, showing an iridescent color range and demonstrating clear crystal form. Size is to 7-8 mm.