A small cabinet specimen of classic Chalcopyrite variety Blister Copper with Bornite. From the Tincroft Mine, Cornwall, England. The Chalcopyrite shows the variety to advantage, and is covered on the display face by a micro-crystal druse of Bornite. The Bornite giving the specimen an iridescent blue/purple colour. On the underside of the specimen the Blister Copper has a more stalactitic form. A specimen showing the variety to advantage.