They looked deep into her eyes and found.... letters...?
Yep! Letters. Seems DeVinci left us a puzzle:
"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.
ARTICLE FOUND HERE
And ANOTHER ARTICLE HERE
That sneaky man him! lol!