This is a 1980 UNC penny from the Phil. Mint. Note the darkened residue at various locations. There is a large mass of this residue just above the ear. Does anyone have any idea of what this residue might be?
It's a bit difficult to tell from that photo, which is too bight to show the spots very well. Maybe post a couple with lighting from different directions. Appears to be contamination spots, but of what, I'm not sure.
To Idhair, How much heat do you suppose is produced when a finished coin drops out of the die? Do you think there is enough heat to burn and carbonize any organic residue? Thanks for responding.
I don't think there is enough heat from minting to cause this. I feel the spots are post mint but it's not really important. It's just damage.
I'm find myself having to accept everyone's knowledge about "carbon spots". The conclusion is that I do not have an "error coin" but I do have a "damaged" coin. Maybe I should write a letter to the U.S. Mint and request that they return the money I paid for this 1980, six coin, uncirculated set.
Several books on the mint says that you can pick the coin up with bare hands after striking if need be. Jim
After 40 years, you may kill some mint worker from laughing. They might replace it the first few months(?) in original packing, but after that it isn't their fault. Jim
