Michigan's Keweenaw Peninsula is the most important locality in the world for native copper. Mining operations began in 1845 and continued until 1968. During that time over 5 million tons of refine copper were recovered from Michigan's native copper mines. Near the turn of the 20th century, Michigan led the world in copper production and "Lake Copper" was the purity standard to which other refined copper was compared.
Michigan Copper Ore Bookends
Pair Measures 5.25" X 8.0" X 1.7", 12.0 lbs.