People of the Waters - Paleoindian
OPM #:
NC-830
Object Name:
Mineral
Description:
Copper Erratic. Erratics are glacially transported stone that have been deposited where the underlying bedrock is a different lithology from that of the glacial stones. Smoothed surface and the presence of striations is evidence of glacial transport. Estimated to weigh 350 pounds.
Comments:
This piece of almost pure copper is known as "float copper." It weighs 350 pounds. Copper nuggets like this were scraped from copper veins around Lake Superior by glacial ice and dragged south along with other rocks. The ice smoothed the copper as it was dragged and rolled. Scrape marks can sometimes be seen on these pieces. When the Earth warmed and the glaciers melted and retreated northward, the copper and rocks remained.

Float copper has been found in eastern and southern Wisconsin and as far south as southern Illinois. Most float copper is small, but pieces can be huge. The largest known float copper weighed an amazing 25 tons.
Material:
Metal
Dimensions:
H-15.5 W-33 L-64.5 cm
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Amy Maile Photography Copyright 2017Amy Maile Photography Copyright 2017