Portrait coin of Ptolemy I

A tetradrachm from circa 305–283 BC. The obverse shows a self-portrait of Ptolemy I wearing a diadem and aegis, and the reverse shows an eagle standing on a thunderbolt, with the legend "ΠΤΟΛΕΜΑΙΟΥ ΒΑΣΙΛΕΩΣ". This is one of the earliest examples of a living ruler placing their own portrait on a coin. The kingdom was the only one of the major successor states to abandon the Attic standard in favor of a lighter standard, and foreign coins were subject to compulsory exchange at royal banks on the border. A papyrus from 258 BC preserves the voice of a mint official writing about the confusion in exchange practices. Photographed at a special exhibition at the Glyptothek in Munich.