Physicist Volker Rose Solves Picasso Mystery Using Synchrotron-Based, X-ray Microscopy

Art historians have long argued over what type of paint Pablo Picasso used to create his famous masterpieces. 

Dr. Volker Rose, a physicist at Argonne National Laboratory in Illinois, has the answer: common house paint.

Dr. Rose is part of a team of scientists and art experts who used synchrotron-based, X-ray microscopy to solve the long-running debate, as he explained to a crowd of 70 people at Ohio University on Aug. 29 during his talk “Shining Light on Nanoscale Materials: From Picasso to the Ultimate Resolution in X-ray Microscopy.”

“This problem has been heavily discussed before.  Picasso was always mixing paints, so it could be misleading for paint experts,” he said. 

Dr. Rose was able to solve this problem by using a hard X-ray nanoprobe to study impurities in single pigments of paint. He and his collaborators from the Art Institute of Chicago then compared those results to original samples of white paint used by Picasso.

The main component of this white paint is zinc oxide, which also happens to be a material physicists study often, as it is used in light-emitting diodes and liquid-crystal displays in computers and TVs.

“Zinc oxide is heavily studied in spintronics.  Scientists know a lot about zinc oxide, but what they don’t realize is that this is the same thing Picasso was using as white paint,” he said.

The beauty of using X-ray microscopy to perform this type of analysis is that the process does not compromise the artifact.

“You do not destroy the samples.  What is special is that we put this technology (synchrotron-based, X-ray microscopy) in an area where nothing has been done before at the nanoscale level,” he said. 

The paint samples taken were as small as a grain of salt.  The X-ray microscope the researchers used allowed them to study the chemical makeup of the paint at a spatial resolution of 30 nanometers, quite miniscule considering that a human hair is approximately 50,000 nanometers thick, or the head of a pin is around 1 million nanometers across.  

Dr. Rose has also used this technique to study the corrosive patterns of daguerreotypes, early photographs created on silver-plated copper plates.

For future work, Dr. Rose’s team has developed a unique method to study nanoscale materials by combining scanning probe microscopy with synchrotron X-rays.  This technique allows an understanding of structure and provides detailed information about chemical, electronic, and magnetic state.

Dr. Rose thinks that his research is a perfect example of how scientists and artists can work together. He saw this project as an opportunity for a new collaborative area of research between scientists and art historians: to use the nanoprobe to study cultural heritage objects under microscopic conditions at the nanoscale level.

Dr. Rose, who is an Early Career Awardee of the U.S. Department of Energy, graduated with a doctorate in physics from RWTH Aachen University in Germany in 2005. He works as a physicist in a joint appointment between the Advanced Photon Source and the Center for Nanoscale Materials at Argonne National Laboratory.