1 Mil Réis Thesouro Nacional, Copper exchange note

Brazil's Thesouro Nacional began issuing copper exchange notes (notas de cobre) in 1833 as a direct response to a chronic shortage of small-denomination copper coinage in the northeastern provinces. The notes were explicitly redeemable in copper coin — not silver, not gold — a distinction that mattered considerably to the poor and working populations who actually handled them. Copper itself was depreciating, which made the exchange promise increasingly hollow as the decade wore on.

Among the earliest paper instruments issued under the Brazilian Empire, predating the establishment of the Banco do Brasil's second charter by several years. The watermark security was rudimentary by contemporary European standards, and counterfeiting of the copper note series was reported almost immediately after issue.