Looking at Leonardo da Vinci’s “La Gioconda” or Van Gogh’s “Sunflowers” or any other figurative work from past centuries, can it be considered the same painting by the painter? Over the years, the paintings have changed. The merciless passage of time modifies it forever.
Some of these changes are provided by Reduction and oxidation processes that metals undergo which are part of the dyes used by artists. For example, white lead (white lead) in the presence of lead sulfide forms, which is black in color.
Van Gogh’s colors
Among the most special cases The immeasurable work of Vincent Van Gogh, a Dutch painter and one of the greatest exponents of Post-Impressionism. Filled with the bold and vibrant colors they display, Van Gogh’s paintings have the potential to attract a diverse audience and delight fans. However, many The colors used in his works have changed dramatically over time. Mainly due to exposure to light. Many of the changes can be attributed to the yellowing that the varnish experiences with age. However, it is clear that the cause of others pigment degradation.
Van Gogh’s works are glorified and extensive, but perhaps among the best known is the “Sunflowers” series of oil paintings. It seems that the first paintings in the series were painted to decorate the bedroom of his friend Paul Gauguin. This famous work was created thanks to The use of new pigments developed during the nineteenth centuryspecifically chrome yellow, which gave sunflowers an incredibly luminous yellow color.
however, At present, the paintings do not show this dark yellow colorIt’s a mysterious, delicious tone midway between yellow and brown. The most accepted theory is that chemical changes occurred in the yellow chromium pigment due to exposure to ultraviolet light. The darkening of the pigments is caused by the reduction of chromium from Cr (VI) to Cr (III). Thus, the darkening of yellow in two other Van Gogh paintings, “View of Arles with Iris” (1888) and “Bank of the Seine” (1887), can be explained by the same phenomenon.
Scientific explanation for his tendency to yellow
In any case, it seems clear that Van Gogh had a preference for yellow, and this shows in much of his work, including paintings such as “The Yellow House”, “Cafe Terrace at Night” or “Alescamps Street” among others.
The painter’s unquestionable penchant for yellow has been linked to digitalis intoxication (Digital Purpurea), which has been used in medicine to treat various diseases. In the time of Van Gogh, Digital has been used to treat manic-depressive crises. The painter used to take it in an attempt to alleviate the seizures that embarrassed his body and mind, to which it was attributed sedative and anti-epileptic properties.
Unfortunately, patients who consumed an excessive amount of digitalis developed xanthopsia, a The pathology that changed the understanding of colors In sufferers, who tend to see things with a yellow tint. Vincent Van Gogh saw the world through a yellow filter Because of the medication he was taking. So the painter transferred only the tones that he had noticed to the paintings.
Digitalis was supplied to Van Gogh by his personal physician, Dr. Paul Gachet. Indeed, in Van Gogh’s portrait of the Doctor, he appeared with a bouquet of digitalis on the table.
However, Dr. Gachet was well aware of the potentially fatal side effects digitalis can cause. s Strongly discourages drug usewhich can produce fainting by slowing the heartbeat and causing organ paralysis.
Moreover, despite the predominance of yellow tones in Van Gogh’s work, yellow in his gallery is always balanced by the use of blue or white, even if it is applied very subtly. With severe xanthopsia, it was difficult to distinguish white and yellow from the painter and blue would have looked green to him. Which will surely follow He was ill to a mild degree.
Other hypotheses It indicates that the painter may have subacute angle-closure glaucoma. This visual ailment would explain the “halos” painted by Van Gogh in some of his works and which are evident in many paintings such as “The Café at Night” or “The Starry Night”.
Specifically, yellow becomes important again in “The Starry Night”. In this work and in “The Road with the Cypress and the Star” and in “The Wheat Field with Crows”, the painter was Capable of capturing fluid turbulence theory with extraordinary certainty which was described by the Russian mathematician Andrei Nikolayevich Kolmogrove in 1941. That is, 52 years after Van Gogh painted The Starry Night.
Of course, Van Gogh’s work continues to preserve unsolved mysteries and demonstrate extraordinary beauty.
* Raul Rivas is Professor of Microbiology at the University of Salamanca. This article was originally published on The Conversation and is published here under a Creative Commons license.