Mona Lisa’s ‘twin sister’ painted by Leonardo da Vinci’s student unveiled

London -  A painting, thought to be the earliest copy of Leonardo da Vinci’s Mona Lisa and painted alongside the original, has been discovered in Madrid’s Prado museum.

The latest discovery, which reveals that the painting was made by a pupil working alongside the painter, may give fresh insight into what the model for one of the world's most famous paintings actually looked like.

The discovery, which is being hailed as one of the most remarkable in recent times, was made during conservation work.

“This sensational find will transform our understanding of the world's most famous picture,” the Telegraph quoted Art Newspaper, which published the findings, as saying.

The Prado painting was long thought to be one of dozens surviving replicas of the masterpiece made after da Vinci’s death but 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. Due of its fragility, cleaning and restoration is thought to be too risky.

However, 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.

“It gives a much more vivid impression of her enticing eyes and enigmatic smile,” the newspaper said.

The discovery of a contemporary copy of the Mona Lisa painted in the same studio of the master and developed alongside the original has been accepted by experts at both the Louvre and the Prado.

The sitter is generally believed to represent Lisa Gherardini, the wife of the Florentine cloth merchant Francesco del Giocondo and is thought to have been painted between 1503 and 1506.

Ana Gonzalez Mozo, a technical specialist at the Prado, presented the findings at a conference on Leonardo da Vinci at London’s National Gallery last month.

She said that what was most exciting about the Prado replica is what it reveals about da Vinci’s original. In the Madrid copy there are areas that are better preserved than in the Louvre painting.