Dear Joe and Board,
I know what you mean, and almost anything is possible, but I have little doubt that Zoser's coin is genuine. In my opinion, it looks as if the coin was clumsily cleaned with something like a scalpel to remove stubborn encrustations and then polished to erase some of the resulting damage.
In Zoser's
obverse photo, the encrustation on the edge of the coin at 3:00 is a detail not often seen on modern casts, at least in my experience.
Best regards,
Mark Fox
Michigan