Æ29 - Antoninus Pius L ΕΝΔΕΚΑΤΟΥ

Year 11 of Antoninus Pius corresponds to 147–148 AD, a period of relative administrative calm in Egypt under the prefect Marcus Petronius Mamertinus. Alexandrian bronze coinage of this regnal year is distinguished by its dating formula — ΕΝΔΕΚΑΤΟΥ marking the eleventh year — a practice unique to the Egyptian provincial system, which reckoned imperial years locally rather than adopting the tribunician dating used on Roman imperial issues. The Alexandrian mint was among the most prolific provincial operations in the empire, yet individual year-dated types can be surprisingly scarce in fine condition given the heavy commercial use Egyptian bronzes sustained in the Nile delta economy.