Reverse Along the edge of the coin is a Latin inscription 'PORTUGALIAE ET ALGARBIORUM REGES', translating to 'Kings of Portugal and the Algarve'. The beginning and end of the inscription are separated at the top by a relief flower with eight petals. In the central part is a wreath formed by two olive branches tied at the base with a bow. Inside the wreath is the Roman numeral 10 'X', separating the mint year '17 85'. Below is a relief four-leaf clover.
Obverse Around the edge of the coin are decorative raised denticles. Along the rim are Latin inscriptions, on the right 'MARIA I ET PETRUS', on the left 'III DEI GRATIA', translating to 'Maria the First and Peter the Third by the Grace of God'. In the central part is the coat of arms of Portugal crowned with an imperial crown: on the heraldic shield are five Spanish escutcheons arranged in the form of a cross with bezants, around the large shield is a wide fluted border with seven castles. The heraldic shield is framed by relief elements in the Rococo style.