The 1797-R Brazil Maria I Half Johannese (6,400 Réis) is a significant gold coin linked to the early 1800s NSW proclamation coinage. Struck in Brazil under Portuguese authority, it features a dignified bust of Queen Maria I on the obverse, engraved by José Gaspard, with the royal arms on the reverse. Valued for its high gold content and international acceptance, this coin was officially assigned a set value in Governor King’s 1800 proclamation. It helped stabilise commerce in colonial New South Wales, where reliable gold coinage was scarce and foreign issues underpinned everyday trade.