I'd like to say a grinder/buffing job but there also appears to be a die crack on the reverse. Let the others chime in here.
1st. nice photos... 2nd. In my humble opinion, this coin merits a visit to a coin show where ANACS is set up. Allow the ANACS person to give you their opinion, you can also ask several other dealers what their opinion is. Keep in mind, opinions may vary
Sounds like if nothing else it is a little bit of a mystery. I will keep an eye out for one of the shows. Thanks everyone.