5 000 Mark Steinkohlenbergwerk Gewerkschaft Neumühl

Zeche Neumühl was a hard coal mine in Hamborn — now part of Duisburg — and like hundreds of industrial concerns across Germany in 1923, it was printing its own emergency money because the Reichsbank simply could not supply currency fast enough to meet payroll. The hyperinflation peaked so rapidly that wages had to be paid in whatever denominations a company could produce locally, often within days of printing.

Mine-issued notgeld from the Ruhr carries particular weight given that 1923 was also the year of the Franco-Belgian occupation of the region, which directly accelerated the currency collapse.