I am sure that my eyes are going buggy from looking at the computer all day. But it kinda looks like a very faint "S" under the date like one was there at one time and got removed. Maybe it is like looking at clouds and finding shapes. Maybe I need a drink.
i see what you saw, but i agree, it looks too big to be a mm. maybe someone tried to add one, realized it looked horrible, and then removed it???
Of course they did. They just used invisible letters as an experiment for the CIA in hiding stuff. But did they ever hide an S on coins?