Stater

Among the earliest struck coins known, the electrum staters attributed to uncertain Ionian mints represent the moment when stamped metal replaced weighed bullion as a medium of exchange — a transition that almost certainly originated in Lydia or the Greek cities of the Anatolian coast in the late seventh century. The precise issuing authority for pieces in Weidauer's Group I remains genuinely unresolved; candidates include Miletus, Ephesus, and Phocaea, but no ancient source definitively assigns early striated or plain-punch staters to any single city.

The electrum itself is naturally occurring, alloyed gold and silver drawn from the Pactolus River deposits in Lydia.