As - Tiberius Countermarked

The countermark on this as almost certainly dates to the reign of Claudius, when a severe bronze shortage in the western provinces prompted official restamping of earlier Tiberian issues to extend their monetary life. Pangerl and Martini's corpus documents dozens of distinct countermark types applied to Julio-Claudian aes, many traceable to specific military units or administrative regions along the Rhine and Danube frontiers.

Countermark #89 in their catalog places this piece within a documented group rather than among the many unofficial or unattributed stamps that complicate the series.