At first, I thought possible dropped letter, but upon enlarging it, that mark has a serf on it and none of the letters on a cent use that type style. So, what is it? Your guess is as good as mine. PMD?
It sure doesn't look like the same font as the mintmark. I think it is just a quirky hit that looks like the part of a letter....PMD! Chris
Not from the Mint. It occurred afterwards. The one close to the rim is cut into the coin do it's not raised.