Reverse Along the upper edge of the coin, an inscription in Latin reads 'PORTUGALIAE . ET . ALGARB . PRINCEPS', which translates as 'Prince of Portugal and the Algarve'. The beginning and end of the inscription are separated at the top by a relief flower. In the central part, a wreath formed by two olive branches tied at the base with a bow. Inside the wreath is the Roman numeral 20 'XX', with the year of minting '1800' below it.
Obverse Around the edge of the coin are decorative raised denticles. Along the rim are inscriptions in Latin: on the right 'JOANNES', on the left 'DEI . GRATIA', translating as 'João by the Grace of God'. In the central part is the coat of arms of Portugal: a heraldic shield crowned with an imperial crown. On the shield, arranged in the form of a cross, are five small Portuguese shields with bezants; around the edge of the large shield is a wide, fluted border with seven castles. The heraldic shield is framed by relief elements in the Rococo style.