Æ34 - Antoninus Pius L ΔΕΚΑΤΟΥ

Year 10 of Antoninus Pius's reign in Egypt — 146/147 AD — places this piece within the prefecture of a province that ran its own dating system, its own coinage, and effectively its own monetary economy, closed to the outside Roman world. Alexandria's bronze issues of this size were not interchangeable with Roman aes; they circulated only within Egypt's borders, a deliberately maintained fiscal boundary that Rome had inherited from the Ptolemies and never dismantled. The Alexandrian mint was one of the most prolific in the empire, yet large-module bronzes of this diameter thin out sharply in surviving collections.