Native Copper: Cliff mine, Phoenix, Keweenaw County, Michigan USA

Description

Species: Native Copper

Locality: Cliff mine, Phoenix, Keweenaw County, Michigan USA

Dimensions: 17 x 14 x 3.5 cm.

The Cliff Mine was the first successful copper producer in the Keweenaw Peninsula Copper District of northern Michigan, and as early as the end of 1845, around 20,000 pounds of mass copper was removed from the shafts and working at the site. A classic “fissure vein” type copper deposit, it was noted for superb specimens of crystallized copper and silver in a variety of morphologies and associations over it’s nearly 100 year period of operation. This is an outstanding large copper specimen for the Cliff mine, featuring robust, blocky, beautifully-patina’d copper crystals to over 5 cm showing a combination of dodecahedral and twinned tetrahexahedral crystal forms. This style of crystallization is very different than the more delicate, ‘herringbone’ spinel-twinned forms I often associate with the fissure vein type copper mines in Keweenaw County, and is more reminiscent of the classic large blocky copper crystals found in some of the major mines to the south such as the Quincy and Franklin mines.

This superb copper specimen is very 3-dimensional and can be displayed in a variety of orientations. It was a great provenance as well, as it was in the collection of the Field Museum (Chicago, Illinois) before passing to noted mineral and mining artifact collection Robert “Bob” Heyrmann. The patina and overall form of this piece is outstanding, and as a Cliff mine specimen it is a great large, hefty example of well-crystallized copper from this important locality. Comes with a custom acrylic display base by the Sunnywood collection. Annette Slade photos. Please inquire for a short video of this specimen.