WHOA! Wicked! Looks like an acid job to me, but it could be a lamination or planchet flaw. How did you find it? Phoenix
I think I found it in the same bag as the 56-D I posted the other day. In fact, I think there was a 11-S in VF in the bag as well. I love going to local estate auctions for bags and rolls of mixed wheat cents. The bigger buyers never bid much for these and I get them at a good price. I feel most older collectors or non collectors who saved these out of pocket change never bothered to look for error's of any type.
I would think this is a glue or type of clear coating placed onto the coin. It appears to have retained some red under the coating. Just my opinion.