2 Gulden Siege coinage, Klippe

Frankenthal was one of the last Palatinate strongholds to fall during the opening phase of the Thirty Years' War. Spanish forces under Gonzalo de Córdoba besieged the city from 1621, and the garrison held out until 1623 — an unusually protracted resistance. Siege coinage was struck from whatever silver the defenders could gather, which is why these klippen exist in multiple weight standards and why KM#9.3 represents just one node in a series of emergency denominations.

The square flan is a direct consequence of speed: clipping sheet silver into rough squares was faster than preparing round blanks.