Some of New Mexico art icon Georgia O’Keeffe’s most well-known paintings have developed troubling signs of deterioration in recent years, and conservators and researchers are working to figure out why.
A partnership between Santa Fe’s Georgia O’Keeffe Museum and a multidisciplinary team of scientists at Northwestern University in Evanston, Ill., has discovered that many of O’Keeffe’s paintings, particularly those made between the 1920s and 1940s, have and are continuing to develop tiny soapy protrusions, some even numbering in the hundreds per painting.
Most of these micron-sized “blisters” — once thought by conservationists and scholars to have been grains of sand swept onto the canvas from the New Mexico desert where O’Keeffe worked — are invisible to the naked eye, but they are growing, pushing up the paint and either warping the surface or piercing through.
According to Marc Walton, a research professor of materials science and engineering at Northwestern who co-led the study, metal soaps were created from chemicals in the oil paints O’Keeffe used at the time. Lead and zinc reacted with free fatty acids, forming “something that looks like acne” on the surface of the painting, he said. Varying environmental conditions — such as temperature, humidity or direct sunlight — also might have had an impact, and research is ongoing.
Walton’s team estimates that perhaps 70 percent of all oil paintings have soaps in them, but most are benign.
“It’s only in certain conditions which we get the protrusions on the surface of the canvas,” Walton said.
Dale Kronkright, head of conservation at the O’Keeffe Museum, has been working on the issue for several years. He said in a statement that there appears to be a correlation between the number of times the affected paintings have traveled to public exhibitions and the spread of deterioration. Conservators have restored some of the worst damage, but it continues to return.
“The more times the paintings have traveled, the more likely it will be that the protrusions are larger and more numerous,” Kronkright said.
Notable O’Keeffe works such as Pedernal (1941) and White Bird of Paradise (1939) have been affected, according to museum spokeswoman Micaela Hester, who said that although the deterioration is happening quite slowly, the museum has taken the issue very seriously.
“It is our job to protect these paintings, full stop,” Hester said. “And that is why we are always pushing our conservation and innovation.” Hester said that museum conservators are confident they will be able to minimize the damage.
In addition to the museum’s restoration work, Kronkright has developed special display frames that create their own microclimate in order to prevent paintings from further degradation due to temperature, moisture or light, Hester said.
Another innovation, arising from the Northwestern team’s research, is a method of detecting the flaws more easily and quickly, using a computer tablet with an app that reflects light off the surface of the painting and analyzes it. Current techniques that are similar typically involve larger, more cumbersome and expensive equipment. The hope is that this new tool will allow other museum conservators who face similar challenges with their paintings access to the technique.