5 Sen - Meiji

KM#Pn28 designates this as a pattern strike, not a circulation issue — the 1888 copper-nickel 5 sen was part of Japan's ongoing evaluation of coinage materials during the Meiji government's push to modernize its monetary infrastructure along Western lines. The Osaka Mint, which had been established with British technical assistance in 1871, tested multiple alloy compositions throughout the 1880s before settling on production specifications.

Copper-nickel patterns from this period are genuinely scarce; most were retained by the mint or distributed to officials rather than released.