Copper, Northwestern Mine, Lake Superior Copper District, Keweenaw County, Michigan Miniature 3 x 4 x 6 cm $3500. Online 4/29
The Northwestern Mine was operated on one of the smaller transverse fissures that cut the amygdaloid belt at nearly right angles in the Keweenaw Peninsula. It was never a major copper producer in terms of tonnage but it did produce a number of superb copper specimens. This piece is just such a fine quality miniature with beautiful rich brown patina, very sharp crystals and no point of attachment. Really an excellent specimen. Mined c. 1860s-1870s. Paul Labonte Collection.