Given the photos posted it appears to be the result of post strike damage. The coin didn't leave the striking chamber with a sunken mint mark protruding into the reverse. A sharp close-up of the mint mark, taken at a slight angle, might help. Thanks.
A deep strike would make the mm higher, not lower. As stated, it has been struck with a punch or something similar. Just a damaged coin now worth 10 cents.
I also thought that, a small punch used. After reflection I would think it highly unlikely since the pressure needed would have flattened the mint mark. Am I missing something? I'll experiment with a hammer and 1/16 punch with the results.
ANA member - PAN Member - BCCS Member There are no problems only solutions - the late, great John Lennon
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