Scientists took a microscopic flake of paint from the pond in Van Gogh's Wheat Stack Under a Cloudy Sky (shown on the left) and found that beneath the surface the vivid red lead pigment originally used remained (top right and bottom right) but had degraded to grey and white colour on painting's surface (bottom centre) Descriptions by Van Gogh of the colour of his lodgings that he painted in The Bedroom show that the floor and walls actually contained more red pigment, giving them more vivid shades than they have today .
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