Nice pickup! I have always liked these.
Likely the monogram often seen on Ptolemy II's from the Alexandreia mint, sort of a sideways "M". For comparison I've tried to lighten yours and place it alongside two examples:

Quote:
I can't determine the mark above the shield.
I can't determine the mark above the shield.
Likely the monogram often seen on Ptolemy II's from the Alexandreia mint, sort of a sideways "M". For comparison I've tried to lighten yours and place it alongside two examples:






















