80 Réis Countermarked on 40 Réis - José I - Angola

In 1809, the Royal Treasury in Rio de Janeiro — operating from Brazilian soil following the Braganza court's flight from Napoleon's invasion — ordered existing copper coinage to be countermarked and revalued to address acute small-change shortages across Portuguese colonial territories. Angolan 40 Réis pieces were punched with a new mark doubling their face value to 80 Réis, a monetary expedient that avoided the cost and delay of striking entirely new coin.

The countermark itself was applied with varying force and placement, meaning no two pieces align identically on the host coin.