Year 12 of Diocletian's reign (294–295 AD) coincides almost exactly with his sweeping monetary reform of 294, in which he introduced the argenteus and restructured the billon nummus across the empire. Alexandria, however, operated under a separate reckoning — the Egyptian regnal year system — and continued producing tetradrachms in debased billon well into this transitional period, running parallel to the reformed coinage rather than replacing it immediately. The Alexandrian mint was among the last to fully integrate into the standardized imperial system.
Year 12 of Diocletian's reign (294–295 AD) coincides almost exactly with his sweeping monetary reform of 294, in which he introduced the argenteus and restructured the billon nummus across the empire. Alexandria, however, operated under a separate reckoning — the Egyptian regnal year system — and continued producing tetradrachms in debased billon well into this transitional period, running parallel to the reformed coinage rather than replacing it immediately. The Alexandrian mint was among the last to fully integrate into the standardized imperial system.