By itself, trade with Elmina caused royal revenues to nearly double in Portugal during the last twenty years of the fifteenth century. By 1506, with the tentacles of Portuguese empire already enveloping Brazil and reaching deep into Asia, gold from the Elmina region still constituted fully a quarter of crown revenue. The Gold Coast was generating about 680 kilograms of gold per year for Portugal or, it has been estimated, about a tenth of the entire known total world supply around that time.
