However, because the Ritsuryo system had already collapsed at the time and the technology to mint coins as well as the office in charge fell into disuse, Japan had to import copper coins from China to distribute domestically.
しかしながらその時代には律令体制が崩壊しており、銭貨鋳造を行う役所も技術も廃れていた事から、中国から銅銭を輸入してそれを国内で流通させていた。