The Old Copper Complex is most likely a manifestation of the Woodland Culture, but is pre-pottery in nature. This population is believed to be the oldest in Wisconsin, and existed nearly 5000 years ago. The name "Old Copper" comes from their use of Lake Superior copper for tools and ornaments. This type of copper is easily recognized, due to its 99% purity level with only slight traces of iron, silver, cobalt, arsenic and nickel.

There are several processes used to shape copper. Hot hammering requires the individual(s) to heat the copper before hammering or molding it into the desired piece. Cold hammering does not require heat to shape the copper into the tool or ornament..

There have been many copper artifacts found throughout several Wisconsin sites. The implements that have been uncovered include awls, spear points, fishhooks, knives and harpoons. Copper spuds have been found as well. The spuds are especially interesting because of the large number found and because they appear to have had an implemental, as opposed to ornamental, use.

Ornamental artifacts include beads, a clasp or clip, bracelet, rings, crescents and celts. Sixty beads, found at the Reigh Site, were strung together in what appears to be a necklace. All copper artifacts were covered with a heavy green patination due to the formation of copper salts.

The Copper Culture is linked to the Woodland Culture based on the copper artifacts found in the Effigy Mound Aspect. Most notable are the "square in cross-section" or "round in cross-section" awls. The square in cross-section awls are also found in Hopewellian Culture. Although rare, copper artifacts have also been found in the Mississippian Culture.

Image Credit: The State Historical Society of Wisconsin

References:

Ritzenthaler, Robert E. and Warren L. Wittry. "The Oconto Site-An Old Copper Manifestation". Wisconsin Archaeologist, 1957.

Ritzenthaler, Robert E. "The Osceola Site-An Old Copper Site Near Potosi, Wisconsin." Wisconsin Archaeologist, 1946.

Ritzenthaler, Robert E. with reports by Neil J. Ostberg and Phil Wiegand. "Reigh Site Report Number Three." Wisconsin Archaeologist, 1957.