
, you have come to the right place!
It almost looks like a worn die issue than a mint error on a very common date
Buffalo nickel. Also that little letter F that was indicated in your title is not a mintmark, but rather the initial of the designer of said nickel, James Earl Fraser in 1913. The mintmark is always on the reverse between the two words Five Cents and could have a D for Denver and a S for San Francisco. No letter like yours is Philadelphia minted.
As to grade, estimated Very Fine (VF-20) details cleaned...

Hope this helps clarify a little
