How the Mona Lisa Lost Her Eyebrows

Pascal Cotte said Leonardo built the painting up in layers, the last being a special glaze whose optical properties increased the illusion of a three-dimensional face. Above the glaze Leonardo painted details such as the eyebrows. Cotte said: “That could explain why the eyebrows have disappeared – they have faded because of chemical reactions or they have been cleaned off.” He has uncovered a host of secrets about the Mona Lisa using a 240 megapixel camera. It can measure light [...]