| | |  Native Copper, Caledonia Mine. This is a heavy lump of naturally occurring copper from the Caledonia Mine, Ontonagon County, Michigan.  Like several of the dozen samples I got from the same source, this one has what look like impressions of pebbles, as it was compressed around them at some point in its history.
 Source: Larry Curtis
 Contributor: Theodore Gray
 Acquired: 10 June, 2003
 Price: $2.50
 Size: 2"
 Composition: Cu
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