Species: Native Copper, Cuprite, Malachite
Locality: National Mine, Rockland, Ontonagon Co., Michigan, USA
Dimensions: 17 x 6.8 x 5 cm.
The National mine, located in the southern part of the iconic Lake Superior Native Copper District in Michigan’s Keweenaw Peninsula, was a relatively small underground copper mine which was operated intermittently from 1848-1893. While it produces the same outstanding crystallized specimens of native copper and silver as most other Keweenaw Peninsula mines, one unusual attribute to the National mine is the assemblage of supergene copper minerals including cuprite, malachite, and azurite found there, which are in general quite unusual for the Keweenaw.
This exceptional large cabinet-size copper specimen features sharp dodecahedral crystals to nearly 2 cm which would make it a superb specimen alone, but what really makes this piece special is the rich, lustrous, deep wine-red cuprite patina of the copper crystals. This type of thick, lustrous cuprite patina is extremely unusual in Michigan copper specimens in my experience. One end of the specimen even has masses of crystallized cuprite adhering to the copper, as well as minor malachite. This superb old classic likely was mined in the mid to late 19th century, and was in a museum in Scandinavia before returning to the States to be part of the noted collections of Steve Whelan, Ross Lillie, Paul LaBonte, and Ben Vone. A fabulous large copper with a great patina, great form, and great provenance. Comes with a custom acrylic display base by the Sunnywood Collection. Annette Slade photo.