Mona Lisa
The painting is thought to be a portrait of Lisa Gherardini, the wife of Francesco del Giocondo, and is in oil on a white Lombardy poplar panel. It had been believed to have been painted between 1503 and 1506; however, Leonardo may have continued working on it as late as 1517. Recent academic work suggests that it would not have been started before 1513. It was acquired by King Francis I of France and is now the property of the French Republic, on permanent display at the Louvre Museum in Paris since 1797.
Speculations about Mona Lisa
It has been suggested that Leonardo created more than one version of the painting. Another contender is the "Isleworth Mona Lisa", which had been hidden in a Swiss bank vault for 40 years before being unveiled to the public on September 27, 2012. The Swiss Federal Institute of Technology in Zurich has dated the piece to Leonardo's lifetime, and an expert in sacred geometry says it conforms to the artist's basic line structures.