u/ThrobbyLobby

I am familiar enough with coin collecting to know the terminology, but still otally confused when it comes to differentiating between errors and their details. This is the one coin I haven't been able to get to clear answer from any AI or Google image search. The area where the mint mark should be it's just as confusing in person as it is in pictures. I've tried adjusting contrast and everything but I can't figure out if it's a partial letter or what, it is raised up.