La Belle Ferronnière () is a portrait of a lady, usually attributed to Leonardo da Vinci, in the Louvre. It is also known as Portrait of an Unknown Woman. The painting's title, applied as early as the seventeenth century, identifying the sitter as the wife or daughter of an ironmonger (a ), was said to be discreetly alluding to a reputed mistress of Francis I of France, married to a certain Le Ferron. Later she was identified as Lucretia Crivelli, a married lady-in-waiting to Duchess Beatrice of Milan, who became another of the Duke's mistresses. Leonardo's Lady with an Ermine has also been known by this name. This was once believed to be a portrait of Cecilia Gallerani, one of the mistresses of Ludovico Sforza, Duke of Milan. The narrative and the title were applied to Lady with an Ermine when it was in Princess Czartoryski's collection, and became confused with La Belle Ferronnière by the presence in this image also of a jewel worn on a delicate chain across the forehead, called a ferronnière. This painting was on loan in Louvre Abu Dhabi, UAE in 2017. Attribution Although the model of the painting La Belle Ferronnière is still shrouded in mystery, the landmark exhibition "Leonardo Da Vinci: Painter at the Court of Milan" (National Gallery, London, 9 Nov. 2011 – 5 Feb. 2012) listed the portrait as possibly depicting Beatrice d'Este, wife of Ludovico Sforza. This challenges an earlier identification of the sitter as Lucrezia Crivelli, a mistress of Ludovico. Karl Morgenstern (1813) and other critics noted some similarities with the drawing number 209 preserved in the Uffizi, executed in lapis and watercolor but retouched a little hard everywhere by a hand of the sixteenth century, which was identified by Father Sebastiano Resta (XVII century) as a portrait of Beatrice d'Este and attributed to Leonardo da Vinci . So also Dalli Regoli (1985), who considered the drawing the copy from a lost original by Leonardo. Bernard Berenson attributed this portrait to Bernardino de' Conti. Giovanni Antonio Boltraffio was suggested by Herbert Cook, who retracted his opinion, seeing Leonardo's own hand, in 1904. Copies A later version of the painting, on canvas, had been offered to the Kansas City Art Institute as the original, but was identified as a copy, on the basis of a photograph, by Sir Joseph Duveen, who permitted his remarks to be published in the New