A Spanish sweetshop owner was counting cash in his till in the city of Aviles when he came across a coin bearing the likeness of Homer Simpson instead of Spanish King Juan Carlos, Reuters reported.
"The coin must have been done by a professional, the work is impressive," Jose Martinez told Reuters.
The carver didn't touch the other side of the one euro coin, displaying the map of Europe, Reuters reported.
"I've been offered 20 euros for it," Martinez said.
Reuters reported no other coins bearing the likeness of Simpson have been found in circulation.