Van Gogh's paintings were discolored because of ultraviolet rays

Scientists have identified the reason for the bright yellow color on some Vincent Van Gogh paintings turned brown.

A picture of Vincent Van Gogh.

It is due to the complex chemical reaction under the sun and ultraviolet rays, which is responsible for this phenomenon.

Sunlight could only penetrate a few micrometers into the painting, but with such a short distance, the researchers found that light rays could produce an unknown chemical reaction, turning yellow chrome brown, changing the original color structure.

Scientists have used small X-ray rays to discover the chemical reaction that takes place on a thin surface, where color meets protective paint. New types of pigments of modern times like gold from chrome allow Van Gogh to produce bright colors as in his sunflower paintings.

The finding is the first step in understanding how to prevent some of the most famous Dutch paintings from being discolored over time.