Hamburg struck this pattern in 1922 as the Weimar government scrambled to find workable substitutes for silver coinage, which had vanished from circulation entirely. Nickel-plated iron was one of several compositions tested across multiple German states and municipalities that year — most never advanced beyond pattern stage. KM#Pn31 is among the handful of documented Hamburg trials from this period, almost certainly produced in very small numbers for evaluation rather than public release.
Hamburg struck this pattern in 1922 as the Weimar government scrambled to find workable substitutes for silver coinage, which had vanished from circulation entirely. Nickel-plated iron was one of several compositions tested across multiple German states and municipalities that year — most never advanced beyond pattern stage. KM#Pn31 is among the handful of documented Hamburg trials from this period, almost certainly produced in very small numbers for evaluation rather than public release.