Æ33 - Antoninus Pius L Κ

This piece belongs to regnal year 20 of Antoninus Pius — rendered as L Κ in Greek numerals — placing it in 156/157 AD, the final stretch of a reign that would ultimately run to 161 AD and stand as one of the longest and most administratively stable of the entire principate. The Alexandrian mint under Roman administration dated its bronzes by regnal year rather than consulship, a bureaucratic convention inherited from Ptolemaic practice that makes precise attribution straightforward where it is often murky on provincial issues.