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.
Mona Lisa
The use of bulletproof glass has shielded the "Mona Lisa" from subsequent attacks. In April 1974, while the painting was on display at the Tokyo National Museum, a woman sprayed it with red paint as a protest against that museum's failure to provide access for disabled people. On 2 August 2009, a Russian woman, distraught over being denied French citizenship, threw a ceramic teacup purchased at the Louvre; the vessel shattered against the glass enclosure. In both cases, the painting was undamaged.