40 Réis - Maria I and Pedro III (Low, Medium and High Crowns; Lisbon)

The 40 Réis coin minted in 1778 during the joint reign of Maria I and Pedro III represents a pivotal era in the colonial history of Brazil. Following the death of King José I, his daughter Maria I and her husband Pedro III ascended to the throne, leading to a brief period of co-monarchy. These copper coins were minted at the Lisbon mint to serve the needs of the Portuguese Empire, including the circulation demands of Brazil, which relied heavily on copper coinage for daily transactions in the colonial economy.

The numismatic classification of this series often references the 'Crown' varieties—low, medium, and high—which refer to the specific positioning of the royal crown above the heraldic shield on the reverse. These design variations were largely the result of the manual die-sinking processes of the late 18th century. While these coins were struck in large numbers to facilitate trade, they remain a significant point of interest for collectors focusing on the transition of the House of Braganza and the administrative changes occurring within the Portuguese maritime empire during the late 1770s.