Chōgin 'Bunsei Chōgin' 6 stamps

The Bunsei Chōgin was issued following the currency reforms of 1820 under the Tokugawa shogunate, part of a broader effort to debase the coinage and replenish depleted bakufu finances. The silver content dropped sharply from earlier issues — the Genbun and Hōreki Chōgin had already set a downward trend, but the Bunsei represents a notable further reduction in fineness. Six verifying stamps indicate this piece passed through the official re-evaluation and stamping process conducted by the za assayers in Edo and Kyoto.

Chōgin circulated by weight rather than by count, which made the declining silver content a slow-burn fraud on merchants who lacked reliable testing equipment.