Locality: Lake Superior Copper District, Keweenaw County, Michigan, USA
Size: 8 x 3 x 3 cm.
An excellent branching cluster of well-formed copper crystals showing well-developed spinel twinning, associated with green prehnite. A great example of well-crystallized copper from the fissure vein type copper deposits of Keweenaw County, Michigan, at the northern tip of the iconic Lake Superior Copper District. Mark Cross photo.
