By using X-ray diffraction and infrared spectroscopy, a team of scientists in France and Britain has detected a rare mineral compound within the iconic piece.
The finding provides fresh insight into how the work from the early 1500s was painted, accordingAlong with lead white pigment and oil, the compound — known as plumbonacrite — was found in the base layer of the paint. Ahad identified the mineral in several 17th-century works by Rembrandt, but researchers had not come across it in works from the Italian Renaissance until the new analysis.
“Everything which comes from Leonardo is very interesting, because he was an artist, of course, but he was also a chemist, a physicist — he had lots of ideas, and he was an experimenter … attempting to improve the knowledge of his time,” Wallez said. The “Mona Lisa,” like many other paintings from the 16th century, was created on a wood panel that required a thick base layer, Wallez said. The researchers believe that Leonardo had made his mixture of lead oxide powder with linseed oil to produce the thick coat of paint needed for the first layer, while unknowingly creating the rare compound.and is protected behind glass, Wallez said.