20 Mil Réis Thesouro Nacional, 4th print

Brazil's Thesouro Nacional turned to Perkins, Bacon & Petch at a moment when the firm's steel-engraved intaglio work was the global benchmark for anti-counterfeiting security — the same London house had produced early postage stamps for Britain and numerous colonial note series. The "4th print" designation marks this as one of several sequential print runs commissioned against the same basic plate design, a procurement approach Brazil used repeatedly during the mid-century period when domestic printing capacity was inadequate for secure currency production.

Mil réis denominations of this era circulated under persistent inflationary pressure; the 1850s saw ongoing debate in Rio de Janeiro over whether the Thesouro Nacional or the Banco do Brasil should hold primary note-issuing authority — a dispute that shaped how these Treasury notes were positioned and retired.