The coins of King Duarte I, known as “the Eloquent”, belong to a short yet meaningful reign within the Avis Dynasty. He ruled from 1433 to 1438, continuing the administrative and economic reforms initiated by his father, King João I. His coinage includes types such as the black real, the white real and the black half real, as well as higher‑value issues that illustrate the development of the Portuguese monetary system in the 15th century. The coins of Duarte I are valued by collectors for their relative rarity, artistic quality and historical significance during the early stages of Portugal’s maritime expansion.