Year 18 of Antoninus Pius's reign, which is what the L ΙΗ formula denotes — the Alexandrian mint dated coins by regnal year rather than consular date, a holdover from Ptolemaic and early Roman provincial practice that makes precise attribution straightforward where Roman imperial bronzes often are not. Alexandria was producing enormous volumes of bronze in this period to service Egypt's essentially closed monetary economy, in which Roman imperial coinage did not officially circulate and local tetradrachms and bronzes handled all everyday transactions within the province.
Year 18 of Antoninus Pius's reign, which is what the L ΙΗ formula denotes — the Alexandrian mint dated coins by regnal year rather than consular date, a holdover from Ptolemaic and early Roman provincial practice that makes precise attribution straightforward where Roman imperial bronzes often are not. Alexandria was producing enormous volumes of bronze in this period to service Egypt's essentially closed monetary economy, in which Roman imperial coinage did not officially circulate and local tetradrachms and bronzes handled all everyday transactions within the province.