Red lead pigment used by Vincent van Gogh has been found to be fading . Impurities in the paint may have triggered a chemical reaction in sunlight . Scientists found a rare lead-based mineral has been forming in the paint . The discovery could help scientists understand how pigments fade over time, and why some colors are more resistant than others.
Red lead pigment used by Vincent van Gogh has been found to be fading . Impurities in the paint may have triggered a chemical reaction in sunlight . Scientists found a rare lead-based mineral has been forming in the paint . This then reacts with carbon dioxide from the air to create white crystals . They warn that many of the artist 's paintings may be at risk of this process . They examined Wheat Stack Under a Cloudy Sky and found it had faded .