Cornado
Cornado is the common name of several Castilian coins made of copper or billon, minted from the time of Sancho IV of Castile until that of the Catholic Monarchs.
The name cornado was derived from the fact that the coin's obverse depicted the crowned head of the king.
In 1286, ten cornados were equivalent to one maravedí, and eight cornados to a. Later versions were coined with a lower alloy quality. This led to the proverb no vale un cornado, equivalent to the English expression "not worth a farthing".