500 Mark Pattern

Germany's 1923 hyperinflation peaked so catastrophically that by November of that year, a single US dollar exchanged for roughly 4.2 trillion Marks. Pattern pieces at this denomination were almost certainly exploratory — the Reichsbank and mint authorities were improvising coinage policy week to week as denominations became obsolete faster than dies could be prepared. Aluminium was attractive precisely because its intrinsic value was negligible, removing the problem of metal hoarding that had gutted earlier issues.

That this pattern apparently never reached circulation is unsurprising; the Rentenmark reform of November 1923 rendered the entire inflated Mark series instantly redundant.