This native copper mass of spinel twinned crystals is from the Quincy Mine in Hancock, Houghton County, Michigan, USA. This mine dates back to the 1846 and was in operation until 1968. It contained 20 different minerals including native copper. This exceptional piece consists of a plate-like formation of complex crystallized copper that divides on the top side into a filigree composed of complex spinel crystals. It measures approximately 3 1/8 x 2 5/8 x 1 3/8 inches or 78 x 67 x 35 mm.