1 Mon 'Kanpyōtaihō'

The Kanpyōtaihō takes its name from the Kanpyō era of Emperor Uda's reign, and it was among the last of Japan's twelve imperially-sanctioned copper cash coins — the Jūnisen — struck before the imperial court abandoned copper coinage entirely for nearly six centuries. The decision to stop minting wasn't gradual deterioration but a deliberate withdrawal: by the late Heian period, rice and cloth had reasserted themselves as the dominant exchange media, and imported Chinese coin filled whatever gaps remained.