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Over the past century, it has been proposed that Mona Lisa was a noblewoman – Isabella d’Este, Marquise of Mantua, or Costanza d’Avalos, Duchess of Francavilla.

Others have stared at that unsettling visage and seen the face of a man – Leonardo da Vinci himself, or...

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These days, most experts agree that the Mona Lisa is a portrait of Lisa Gherardini del Giocondo, wife of a Florentine silk merchant named Francesco del Giocondo (hence the name by which she is known in Italy and France, La Gioconda, or La Joconde). 

When she sat for Leonardo da Vinci, in ar...