4 Mark - Gustav II Adolf Weight of 10 Mark

Reval — modern Tallinn — was a prosperous Hanseatic city under Swedish rule when this piece was struck, and its municipal mint operated with unusual autonomy for a conquered territory. The "Weight of 10 Mark" denomination reflects the Hamburg mark weight standard, which Reval's merchants had used for generations before Swedish annexation and refused to abandon. Gustav II Adolf, deep in the financing demands of his German campaigns that would define the Thirty Years' War, permitted the city's commercial traditions to continue largely intact — monetary pragmatism over imperial standardization.

The KM#5.2 designation distinguishes this from the closely related 5.1 variety.