For decades, archaeologists assumed the black pigments in France's Font-de-Gaume cave were made only from minerals, making them impossible to date. But scientists have now discovered charcoal hidden inside those pigments, revealing that a bison painting is about 13,000 years old and that a mask like figure was created in stages separated by thousands of years.
Charcoal found where none was expected
Font-de-Gaume sits near Les Eyzies in the Dordogne region of southwestern France. It is one of Europe's most famous decorated caves, alongside Lascaux. But unlike Lascaux, the age of its paintings had never been directly measured. Researchers believed the black images were made from iron and manganese oxides, minerals that contain no carbon and therefore cannot be dated using radiocarbon methods. That assumption turned out to be wrong.
A team led by scientists from CNRS analyzed two black figures: a bison and a mask like shape. They used Raman microspectrometry, which identifies materials by measuring how molecules vibrate when hit with light, and hyperspectral imaging, which records subtle color differences across an image. Both techniques detected charcoal mixed into the black pigment. The charcoal was spread evenly through the painted lines, not just in isolated spots.
Two paintings, very different timelines
Because charcoal is made from burned organic material, it contains carbon 14, the radioactive isotope that decays at a known rate. That allowed the team to radiocarbon date the paintings for the first time. The bison was painted roughly 13,000 years ago. The mask like figure told a more complicated story. Different sections of that image were added during several widely separated periods, meaning people returned to the cave over long stretches of time to alter or add to the artwork.
Local residents and archaeologists in the Dordogne have long known Font-de-Gaume as a treasure of prehistoric art, but its exact place in history was unclear. The new dates give them a firmer timeline. They also open a door for studying other caves where black pigments were assumed to be mineral based. The methods used here could help reconstruct when people entered decorated caves, when they made paintings, and when they came back to change them.
A method that could change cave art research
The discovery matters because it solves a problem that had blocked direct dating of many black paintings across Europe. Mineral pigments cannot be radiocarbon dated, but charcoal can. Now that scientists know charcoal can be hidden inside those pigments, they have a way to date artwork that was previously considered undatable. The findings come from a study published by CNRS, the French national research agency, and rely on techniques already used in cultural heritage work, biomedical science, and even astrophysics. For the Dordogne region, the results add a precise chapter to the story of its ancient caves.
