1 Mariengroschen - Ernest I, Botho and Caspar Ulrich

Regenstein was a tiny comital territory clinging to the northern edge of the Harz Mountains, and by the 1560s its ruling house was effectively bankrupt. The joint issue by Ernest I alongside Botho and Caspar Ulrich reflects the county's practice of co-regency among heirs — a legal arrangement that kept the territory nominally unified while forestalling partition. Regenstein was absorbed by Brandenburg-Prussia in 1670, and its independent coinage history is correspondingly brief.

Schult#2891 is among the scarcer documented types from this mint, with surviving examples appearing infrequently in German regional sales.