AR23 - Severus Alexander L ΙΓ

Regnal year 13 of Severus Alexander's reign places this tetradrachm in the period when the emperor was increasingly consumed by pressure on Rome's eastern frontier — Ardashir I had reconstituted Persian power under the new Sasanian dynasty and was pushing aggressively into Roman Mesopotamia. The Alexandria mint continued producing billon tetradrachms at a debased silver content that had been sliding for decades, a quiet fiscal reality the Egyptian monetary system had long accommodated through its closed-currency status: foreign coins could not circulate in Egypt, and Egyptian issues could not leave.