Flor de Sal or Fleur de sel is a salt that forms as a thin, delicate crust on the surface of seawater as it evaporates. Flor de Sal has been collected since ancient times, although it was traditionally used as a purgative and salve. It is now used as a finishing salt to flavour and garnish food. The name comes from the flower-like patterns of crystals in the salt crust. Product of Portugal.