What object does Don Quixote mistake for the helmet of Mambrino?

Don Quixote mistakes a barber’s basin for the helmet of Mambrino.

The episode appears in Part One, Chapter 21, during one of Don Quixote’s imagined chivalric adventures. A barber traveling on a donkey places his metal shaving basin on his head to protect himself from rain. Don Quixote sees the shining object from a distance and interprets it as the enchanted helmet of the legendary Moorish king Mambrino.

Believing the helmet can make its wearer invulnerable, Don Quixote charges the barber and takes the basin. Sancho Panza recognizes the ordinary object, but Don Quixote explains away its appearance by claiming that part of the magical helmet must have been melted down and reshaped. The joke returns later when other characters debate whether the object is a basin or a helmet.

The scene is a classic example of Cervantes’s contrast between Don Quixote’s romantic imagination and Sancho’s practical view of reality.