Thursday, February 17, 2011

Failing Chemistry: When a Good Van Gogh Goes Bad


Around this time of year many high school and college students worldwide come to the sad realization that they’re failing chemistry. To them, a mole will always be just a burrowing mammal. Sometimes Avogadro’s number just has your number. Now, however, those sufferers have distinguished company—Vincent Van Gogh. A team of European scientists have isolated the chemical process that has been turning sunny yellow Van Gogh paintings into somber brown studies over the years. Their findings remind us of how artworks are truly living things, capable of living long after their creator, but also vulnerable to the ravages of time. Please come over to Picture This at Big Think to read more of "Failing Chemistry."

[Image: This illustration shows how X-Rays were used to study why van Gogh paintings lose their shine. Top: a photo of the painting Bank of the River Seine on display at the van Gogh Museum, divided in three and artificially colored to simulate a possible state in 1887 and 2050. Bottom left: microscopic samples from art masterpieces moulded in plexiglass blocks. The tube with yellow chrome paint is from the personal collection of M. Cotte. Bottom right: X-ray microscope set-up at the ESRF with a sample block ready for a scan. Center: an image made using a high-resolution, analytical electron microscope to show affected pigment grains from the van Gogh painting, and how the color at their surface has changed due to reduction of chromium. The scale bar indicates the size of these pigments. Courtesy of ESRF/Antwerp University/Van Gogh Museum.]