Fleur de sel or flor de sal is a salt that forms as a thin, delicate crust on the surface of seawater as it evaporates. Fleur de sel has been collected since ancient times, and was traditionally used as a purgative and salve. It is now used as a finishing salt to flavor and garnish food. The origin of the name is uncertain, but is perfectly in line with both meanings of fleur: flower, and the surface of something. The salt crust forms flower-like patterns of crystals which may contribute to the name.