10 Mil Réis Caixa de Estabilização, overprint on 10 Mil Réis P# 39

The Caixa de Estabilização was a short-lived currency board established in 1926 under President Artur Bernardes, designed to peg the milréis to gold at a fixed rate and restore confidence after years of inflationary financing. Rather than commissioning entirely new notes, the Caixa simply overprinted existing Banco do Brasil stock — in this case the P#39 series already printed by ABNC — with its own authority markings, a pragmatic shortcut that kept costs down but produced a note with two distinct issuing identities on the same sheet.

The stabilization scheme collapsed by 1930, rendered untenable by the coffee price crisis and the Revolution that brought Getúlio Vargas to power. Notes from this series had an exceptionally brief window of official circulation.