six million tons of native copper
A gorgeous specimen from a globally unique giant ore district, producing metal from an abundance of native copper and even more from copper sulphides with many mines in operation between 1845 and 1969. Most of the six million tons of copper recovered from Michigan's upper Keeweenaw Peninsula mining district was drawn into wire. Highly conductive silver-bearing Keeweenaw copper significantly enhanced the electrical and communication networking of North America.
Here on display at the entrance to the AE Seaman Mineral Museum in Houghton, Michigan is ~100 pounds of native copper reaching up from its black basalt base. This fissure vein specimen came from the Pewabic copper lode, Franklin Mine, Hancock.
John Biczok's set of AE Seaman Museum minerals
AE Seaman Mineral Museum website