Year 15 of Antoninus Pius coincided with one of the more stable administrative periods Roman Egypt had seen in generations — the prefect Marcus Sempronius Liberalis was managing the province with enough competence that Antoninus himself wrote to him directly regarding grain supply logistics. Alexandria's billon tetradrachms of this regnal year were struck in quantity, reflecting the mint's role as the sole legitimate producer of coinage for Egyptian circulation, a closed currency system that prohibited outside silver from entering and forced every transaction through locally issued billon of steadily declining fineness.
Year 15 of Antoninus Pius coincided with one of the more stable administrative periods Roman Egypt had seen in generations — the prefect Marcus Sempronius Liberalis was managing the province with enough competence that Antoninus himself wrote to him directly regarding grain supply logistics. Alexandria's billon tetradrachms of this regnal year were struck in quantity, reflecting the mint's role as the sole legitimate producer of coinage for Egyptian circulation, a closed currency system that prohibited outside silver from entering and forced every transaction through locally issued billon of steadily declining fineness.