1 Sen - Taishō

The Taishō era opened with a significant monetary housekeeping problem: the Meiji-period sen coinage had been struck to slightly varying standards across decades, and the new reign offered a clean administrative moment to regularize production. These early Taishō bronzes were struck at the Osaka Mint, which by this point had fully shed its reliance on foreign technical staff — the last British advisors had departed in the 1890s. The three-year window of this type is narrow enough that total mintage across all dates remains modest by Japanese Imperial standards.