Welcome to CT. So, do you think somehow that is a real silver penny? Consider the weight of a cent should be 3.11 g +/- 0.13 g. If it were...
never mind
The edge picture seems to show the Cu/Ni cladding
You did all of that on that poor coin!!!? For milk spots, the only things I would ever trust or do would be acetone/xylene soak/dip and caustic...
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