LXXX Réis '4 Vintens' - Pedro Prince Regent

Pedro governed as Prince Regent from 1668 after forcing his brother Afonso VI into exile — first to the Azores, then to Sintra — in a palace coup backed by the nobility and the Church. The 80 Réis denomination, known popularly as the "4 Vintens" from its equivalence to four 20-Réis vinténs, was among the issues struck under his regency before he formally assumed the throne as Pedro II in 1683 upon Afonso's death.

The .9167 fineness is notably high for Portuguese silver of this period, when wartime expenditure and colonial trade imbalances were already eroding the crown's capacity to maintain consistent alloy standards across its mints.