From Marteau


Japan 1601-1695 (Keicho Era) Gold Ichibu-Kin, weight: 4.5 g, fineness: 84%


Gold coins were minted in units of the ryo, based on the scaling system followed by Koshu gold coins minted under Lord Takeda of Kai province (now Yamanashi Prefecture) See: Dynasties (Japan). Keicho gold coins consisted of the oban (10 ryo), which served primarily as a reward or for ceremonial purposes, and the koban (one ryo) and ichibu-kin (1/4 ryo), which were issued as a means of exchange in daily life. The oban was exchanged according to gold content rather than face value, and was valued at approximately 7.5 ryo.

See Money (Japan)


  • Bank of Japan (ed.) Short Essays on Monetary History Contained in Monetary and Economic Studies, 1-6 Keicho Koban: Establishment of the Unified Currency System link

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