The famous smile of Mona Lisa, the magnum opus of Leonardo da Vinci, is no more a secret as scientists have decoded the technique how the Renaisance-era painter created a special effect to show the enigmatic expression.
According to the experts, the artist managed to achieve his trademark smoky effect, known as sfumato, on the painting by applying up to 40 layers of extremely thin glaze thought to have been smeared on with his fingers.
The glaze, mixed with subtly different pigments, creates the slight blurring and shadows around the mouth that give Mona Lisa her barely noticeable smile that seems to disappear when looked at directly.
With the help of X-rays, the researchers were able to see how the layers of glaze and paint had been built up to varying levels on the face, The Telegraph reported.
With the drying times for the glaze taking months, such effects would have taken years to achieve.
