![Portuguese Empire, Brazil, João V, Dobra, 1730M [ACP4-47] - Image 2](https://colonialcoins.com.au/wp-content/uploads/2026/10/ACP4-47-1.jpg)
Description
Portuguese Empire, State of Brazil, João V ‘o Rei-Sol Português’ (‘the Portuguese Sun King’) of the House of Braganza, Dom of Portugal 1706-1750 AD, Gold Dobra of 12,800 Réis (28.55g, 37mm), 1730 M, ‘Casa de Fundição e Cunhagem’ de Vila Rica (‘House of Casting and Minting of Vila Rica’), Captaincy of Minas Gerais. Obverse: Laureate bust of King João V facing to the right, dies by António Mengin, date and mintmark “M” (Minas Gerais) below, legend surrounds, “IOANNES· V· D·G· PORT· ET· ALG· REX”. Reverse: Royal Arms of the Kingdom of Portugal (comprising five escutcheons in cross, each charged with five plates in saltire, all within a bordure charged with seven castles) surmounted by the heraldic Portuguese Royal Crown, dies by António Mengin which presents the Arms in a highly decorative, cartouche-style frame with elaborate scrolling foliage, ribbons, and flourishes. KM-139. A typically bold example of ‘Johanna’, the “Star” of Philip Gidley King’s Currency Proclamation, typical light contact marks else strong detail and visually attractive, near Extremely Fine.
The obverse Latin legend reads “Iōannēs quīntus, Deī Grātiā, Portucalis et Algarviae Rēx”, which has an English translation of “John the Fifth, by the Grace of God, King of Portugal and Algarve”.
By Alvará on the 4th April 1722 AD, King João V ‘o Rei-Sol Português’ formally established a new ‘escudo-based’ gold coinage system which was centred on one Escudo being equivalent to one Portuguese oitava of 22 quilates (synonymous with carat) of gold, and each Escudo having 1,600 Réis of face value. A host of new denominations were introduced, specifically the ‘Dobra’ of Eight Escudos which had a face value of 12,800 Réis, the proportional Peça of Four Escudos of 6,400 Réis, and proportional fractions including the Meio-Peça of 3,200 Réis, the Escudo of 1,600 Réis, the Half Escudo of 800 Réis, and finally the Quarter Escudo or Cruzadinho of 400 Réis. Each of these new pieces featured a revolutionized design which was far more aligned with the contemporary coinage of Europe – the obverse displayed an elaborate bust of King João V designed by Vieira Lusitano, and the reverse an ornate rendition of the Royal Arms of the Kingdom of Portugal – both dies beautifully engraved by the primary die engraver of the Lisbon mint at the time, the Frenchman António Mengin. A byproduct of the bold obverse portraiture as well as the king’s name “João”, saw the new Escudo series became known as the ‘Joannese series’, with many colloquially referring to the Dobra as the ‘Johanna’ and the Peça as a ‘half Johanna’, and so forth for the fractions. The Dobra was set to a talhe of eight pieces, therefore minted to an intended weight of eight oitavas or one onça, and to the standard 22 quilates gold – metrically speaking, 28.6875 grams of 0.9167 purity. This resulted in an actual gold weight of 26.2969 grams and a ratio of 2.0544 milligrams of gold per singular Réis.
Although a Portuguese coin, the British government assigned the Dobra a face value of 3 pounds 12 shillings due to its frequent circulation in England, and in 1800 AD, it became the largest value monetary denomination chosen by Philip Gidley King, the Governor of New South Wales, for the ’Australian Proclamation’, Australia’s first monetary system – the “star” of King’s Proclamation. In order to retain coinage within the Australian colony, each ‘Proclamation coin’ was given a high face value – the Dobra was revalued to Four Pounds, 8 shillings higher then when used within England.
