Is that Paint or is it Poop?

the-scream Yes, we seriously just asked that question — and, yes, we asked for a good reason.

Have you ever seen Edvard Munch’s famous painting, The Scream? If not, this is a good time of year (being close to Halloween) to check it out. This painting is a haunting depiction of a ghost-faced person standing on a walkway, screaming. It is one of the most recognizable paintings in the world and — having been appraised at nearly $100M — also one of the most expensive.

This masterpiece happens to be at the center of a hot debate within the art community. If you examine the painting closely, you can detect a small white spot on the screamer’s right arm. Believe it or not, this tiny spot has been the topic of much controversy throughout the years. Some have speculated that the spot is in fact bird poop. Many others think that Munch accidentally spilled a bit of white paint on the finished canvas.

chocolate-or-poopFortunately for us, a cultural heritage scientist at the University of Antwerp, Geert Van der Snickt, was unsatisfied going on through life without a definitive answer to the question: paint or poop? With the help of a team of forensic scientists, Van der Snickt began the process of identifying the imperfection. The team started by testing the sample for trace elements commonly found in white pigment. To accomplish this, they used X-ray fluorescence to identify any elements that could positively confirm that the spot was actual paint — but the results were negative.

Next, the team collected a small sample to determine whether or not the spot was instead a bird dropping. Despite previous analysis that concluded that the mysterious blob was not fecal matter, the team sent their sample to a lab in Hamburg, Germany. This lab used the DESY particle accelerator to conduct an X-ray scattering study on the stain. Much to the surprise of the team, a young PhD student, Frederik Vanmeert, identified the crystal structure of the sample. It turns out that sometime after the painting was completed, someone, possibly the artist or just an admirer, spilled candle wax on the painting. Thanks to forensic chemistry, the mystery was solved!

Hey, that’s a fake!

Forensic scientists have been invaluable detectives in the art world for centuries, helping collectors authenticate pieces of art. Sniffing out forgeries is incredibly important, as many of our society’s most famous and priceless cultural artifacts are pieces of art.

One of the ways that scientists identify forgeries is through the study of pigment, and one example of how this discipline has helped to identify art forgeries can be found right here in the United States. The Indianapolis Museum of Art was loaned an Egyptian artifact for one of its exhibits. This artifact’s authenticity was questioned by many observers due to several inconsistencies when compared to similar artifacts from the same time period. Most notably, the hieroglyphs used on the piece were incorrect. To put the controversy to rest, the museum assembled a team of scientists to authenticate the age of the artifact.

This team started by examining the blue pigment found on the headpiece. Egyptians used azurite to create a color known as Egyptian blue, a color that has been found on various Egyptian artifacts dating back to 3000 BC. In the 1800s, French industrial chemist Jean-Baptiste Guimet discovered a way to synthesize a blue pigment that was similar to Egyptian blue, and his synthesized pigment became known as French ultramarine. The investigators’ chemical and microscopic analysis of the sample taken from the headpiece revealed that the pigment used was actually French ultramarine — and not Egyptian blue. Because the scientists knew that French ultramarine was created in the 1800s, they were able to conclude that the artifact was a fake.

Identifying art forgeries is not only incredibly important for collectors, but it helps all of us preserve our shared cultural heritage. The scientists involved in these investigations are heroes for humanity.