Picasso's great works had humble origins: They were painted using house paint, scientists say. Art historians have long debated whether Picasso was one of the first painters to use the standard enamel-based stuff rather than oil paints, but past paint-chip studies couldn't suss out the individual elements with enough precision, reports the New Scientist. In order to finally answer the question, scientists employed an X-ray nanoprobe—a government-developed machine that offers an incredibly detailed look at materials' chemical components.
In this case, they were able to view particles from Picasso's white paint that measured 30 nanometers in width; for comparison, the New York Times reports that a sheet of paper's thickness is about 100,000 nanometers. The scientists bought some house paint on eBay (a 1930s brand called Ripolin) that dated to around Picasso's era, and compared its levels of zinc oxide and iron to those in Picasso's paint. They were a match.