The X-ray picture of the famous painting by Vincent van Gogh "Sunflowers" from the museum of the artist in Amsterdam showed that the sensitive paint used by him for the image of petals and stems gradually loses saturation.

In a two-year study commissioned by the museum, it was found that Van Gogh used two different types of yellow pigment. One of them is subject to greater degradation because of the chromium contained in it, which darkens when exposed to light.

While color changes are almost invisible to the naked eye, and to predict how the shades will change in the future, it is difficult, because, according to the expert from the University of Antwerp Frederic Vanmert, it depends on many factors.

Separate fragments of Van Gogh painting over time, on the contrary, can brighten.

"On small plots the artist used emerald green and red paint with lead, these plots may become lighter in the future," the expert notes, quoted by theartnewspaper.

About the color changes in the paintings of impressionists and post-impressionists experts from Belgium and France reported three years ago, linking it with the use of yellow cadmium in colors. To minimize damage, they called on the museums that own the paintings of these artists, to reduce the illumination in the halls, which a few years ago was done at the Van Gogh Museum.