Van Gogh's changing colours

Art historians are discovering that one consequence of Vincent Van Gogh’s poverty is that many of his paintings do not look today as they did when he first painted them. In particular, many of his areas of red are gradually turning white.

Wealthier contemporary artists were able to use high-quality pigments in their paint, but Van Gogh lived a hand-to-mouth existence for most of his life, depending largely on the generosity of friends to keep him alive. When the urge to paint seized him, he had to use the cheapest materials that he could find.

For his red colours he used red lead, which is a pigment that has been known since ancient times. Unfortunately, when exposed to light the compounds in red lead that give it its colour break down to a mineral that reacts with carbon dioxide to produce two white-coloured compounds.

The degradation can be seen in Van Gogh’s 1889 “Wheat Stack Under a Cloudy Sky” (see above) in which floating leaves have changed from red to white.

Another problem has been noted with the purple-grey colouring in his “Head of an Old Woman with a White Cap” (1885). Vogh Gogh used a pigment based on cochineal, but this has now weathered to a greenish tinge.

Of course, nothing can change the artistry of Van Gogh’s work, and his genius can never be dimmed by a mere change of colour, but it has to be recognised that what we see in the world’s art galleries now is not what the artist saw when he first stepped back from the finished works.

© John Welford