20 Mil Réis Thesouro Nacional, Copper exchange note

Brazil's copper exchange notes — cédulas de cobre — were introduced as a direct response to a severe shortage of copper coinage in the early 1830s. The newly independent empire was hemorrhaging coin through hoarding and export, and the Treasury issued these notes as redeemable substitutes, each theoretically backed by an equivalent value in copper held in reserve. The scheme was immediately controversial; redemption infrastructure was inadequate, and public confidence in the paper was thin from the start.

By the late 1830s the copper reserve fiction had largely collapsed, contributing to inflationary pressure that plagued the imperial monetary system for years afterward. The 1833 series represents the mechanism at its inception, before the full weight of that failure became apparent.