Don't know where you found a denomination 3 falus. The weight standard of those days are:
1 falus - 2.88 gram
2 falus - 5.77 gram
4 falus - 11.54 gram
Your coin is somewhat leprous, parts have fallen off, so 9.5 gram is acceptable for a 4 falus.
A 3 falus would theoretically have been something like 8.65 gram, had it existed. Whoever called it a 3 falus might have been confused by light weight imitations made to be worn on clothes. Or it could be a typo.
Incidentally, mint is Fes.
Peter
