Year 20 of Antoninus Pius's reign, which is what the L Κ reverse date signifies — the Egyptians reckoned imperial years by the regnal count rather than the Roman consular calendar. Alexandria's civic bronze coinage operated as a closed currency system; Egyptian provincials could not legally use Roman imperial coinage directly, forcing exchange at the border and giving the Alexandrian mint unusual autonomy over local monetary supply well into the third century.
Year 20 of Antoninus Pius's reign, which is what the L Κ reverse date signifies — the Egyptians reckoned imperial years by the regnal count rather than the Roman consular calendar. Alexandria's civic bronze coinage operated as a closed currency system; Egyptian provincials could not legally use Roman imperial coinage directly, forcing exchange at the border and giving the Alexandrian mint unusual autonomy over local monetary supply well into the third century.