http://agathe.gr/democracy/athenian_currency.html
Athenian Currency Many of the specialized administrative boards have left material traces of their activities. Most prolific of these were the moneyers, or Overseers of the Mint. Throughout her history ... The New Style coinage, introduced in the Hellenistic period, modernized the representations and added the amphora (oil jar) and names of officials. 32. Plan of the Mint, southeast corner of the Agora, ca. 400 B.C. Found in the neighborhood of the building now identified as the Mint (32) (southeastern corner of the Agora), a bronze rod and blanks cut from it (33) show one of the early stages in the manufacture of coins. ... An inscribed law of 375/4 B.C. describes the procedure to be used to prevent counterfeit money from circulating in the Agora: “Resolved by the Nomothetai, in the archonship of Hippodamas; Nikophon made the proposal: Attic (Athenian) silver currency is to be accepted when [it is shown to be] silver and bears the official die.