2 000 000 000 Mark Rotthausen; Bergwerks-Gesellschaft Dahlbusch

Dahlbusch was one of the major coal mining operations in the Ruhr coalfield, and like hundreds of German industrial firms during the hyperinflation of 1923, it issued its own emergency currency — Notgeld — to meet payroll when the Reichsbank simply could not supply enough physical notes fast enough. The two-billion-mark denomination places this firmly in the autumn 1923 collapse, when denominations that would have been unimaginable in January were routine by October.

The watermarked paper is worth noting — many coal company issues of this period were printed on plain stock with no security features at all, suggesting Dahlbusch was still trying to discourage forgery even as the currency itself became worthless within days of issue.