Isleworth Mona Lisa
According to Leonardo's early biographer Giorgio Vasari, Leonardo had started to paint "Mona Lisa" in 1503, but "left it unfinished". However, a fully finished painting of a "certain Florentine lady" surfaced again in 1517, shortly before Leonardo's death and in his private possession. The latter painting almost certainly is the one that now hangs in the Louvre. Based on this contradiction, supporters of the authenticity of the "Isleworth Mona Lisa" claim it is the unfinished "Mona Lisa", made at least partially by Leonardo, and the Louvre "Mona Lisa" a later version of it, made by Leonardo for his own use.
Speculations about Mona Lisa
In 2004, experts from the National Research Council of Canada conducted a three-dimensional infrared scan. Because of the aging of the varnish on the painting it is difficult to discern details. Data from the scan and infrared were used by Bruno Mottin of the French Museums' "Center for Research and Restoration" to argue that the transparent gauze veil worn by the sitter is a guarnello, typically used by women while pregnant or just after giving birth. A similar guarnello was painted by Sandro Botticelli in his "Portrait of Smeralda Brandini" (c. 1470/1475), depicting a pregnant woman on display in the Victoria and Albert Museum in London. Furthermore, this reflectography revealed that "Mona Lisa"'s hair is not loosely hanging down, but seems attached at the back of the head to a bonnet or pinned back into a chignon and covered with a veil, bordered with a sombre rolled hem. In the 16th century, hair hanging loosely down on the shoulders was the customary style of unmarried young women or prostitutes. This apparent contradiction with her status as a married woman has now been resolved.