“Float” copper is found throughout the “Copper Country” of Michigan and many nearby states. Glacial movements thousands of years ago altered the geological deposits of the native copper by tearing and scouring the land. Copper, along with other rocks, gravel and sand were constantly tumbled and deposited over large areas of the Upper Midwestern United States. Exposure to the soils, water and air has oxidized the copper surface a bright green. These specimens with the natural oxidation color, provide a good contrast to the polished copper surface of the cross-sections.