AR20 - Diocletian ΕΤΟΥϹ Γ

This tetradrachm dates to Diocletian's third regnal year in Egypt, a province that retained its own closed currency system long after the rest of the empire had abandoned it — foreign coins could not legally circulate there, and Egyptian coins could not legally leave. Diocletian would eventually abolish this system entirely in 296 AD, forcibly integrating Egypt into the imperial coinage and ending nearly three centuries of Alexandrian monetary autonomy. Issues from his early reign, before that reform, represent the last generation of a tradition stretching back to the Ptolemies.