Highly magnified images of the painting reportedly reveal tiny letters embedded into the "Mona Lisa's" eyes, reports the U.K.'s Guardian newspaper.
"Invisible to the naked eye and painted in black on green-brown are the letters LV in her right pupil, obviously Leonardo's initials, but it is what is in her left pupil that is far more interesting," said Silvano Vincenti, chairman of Italy's National Committee for Cultural Heritage.
"It is very difficult to make them out clearly, but they appear to be the letters CE, or it could be the letter B," Vincenti added.
In what could be a chapter out of Dan Brown's book (and the 2006 film) "The Da Vinci Code," more mysterious letters and numbers are found on the "Mona Lisa." Vincenti believes these are deliberate hints as to the actual identity of the model who posed for da Vinci's masterpiece -- a mystery that has puzzled art historians for centuries.
"Under the right-hand arch of the bridge seen in the background, Leonardo also painted 72 or L2, another possible clue," Vincenti said. "Two expert painters we consulted on this tell us that all these marks, painted using a tiny brush and a magnifying glass, cannot be an error."
Earlier this year, French researchers, using X-ray technology, determined that da Vinci used as many as 30 layers of paint to achieve the subtle shadows and light on the beguiling Mona Lisa face.
While that technology helped solve the mystery of how the "Mona Lisa" was created, her identity is an ongoing mystery, even though some historians are convinced she was Lisa Gherardini, the wife of a prominent merchant of Florence.
Vincenti, who will offer his conclusions about this new research next month, said it all began after a colleague found a decades-old book that referred to the letters in "Mona Lisa's" eyes.
"Leonardo was keen on symbols and codes to get messages across, and he wanted us to know the identity of the model using the eyes, which he believed were the door to the soul and a means for communication," Vincenti said.
Read more at The Guardian.
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