PARIS -- There's something vaguely familiar about this charcoal sketch of a woman's face and nude torso -- could it be an unclothed precursor to the Mona Lisa?
French government art experts are trying to find out, analyzing the sketch in a laboratory beneath the Louvre Museum to see if Leonardo da Vinci himself drew it before painting his 16th century masterpiece.
The sketch, previously attributed to Leonardo's students, is part of a collection at the Musee Conde du Domaine de Chantilly museum north of Paris. Museum curator Mathieu Deldicque said on BFM television Friday that there are signs it was drawn by Leonardo himself.
He noted the position of the subject's hands, and the "enigmatic smile." But he acknowledged differences, including the way she holds her chest and the hairstyle.
The Mona Lisa oil painting, among the world's greatest art treasures, hangs in the Louvre.
Art historians believe Leonardo drew or painted a nude version of the Mona Lisa. Deldicque acknowledged that the belief is feeding hopes that the Chantilly museum's sketch was indeed made by Leonardo's hand.
"We know that da Vinci created a nude version," the curator said. "We don't where the work of the master is."
"There are two mysteries" around this sketch, he said. "The author, and the meaning of this nude Mona Lisa."
The government-run Center for Research and Restoration of the Museums of France says its experts are studying the sketch and that it will stay out of the public eye until the examination is complete.
