The Prado painting was long thought to be one of dozens surviving replicas of the masterpiece made after Leonardo’s death but it is now believed to have been painted by one of his key pupils working alongside the master.
The Louvre original, displayed behind glass, is obscured by cracked darkened varnish, making the woman appear much older than her true age. Because of its fragility, cleaning and restoration is thought to be too risky.
But art historians believe the Prado’s Mona Lisa which is in the process of being painstakingly stripped of a dark over-paint reveals her as she would have looked at the time.
Story: Fiona Govan, Telegraph | Photo: Museo Nacional del Pradio