A four-part prehistoric complex
The Grotte du Pech de l'Azé is not a single cave but a complex of four distinct sites, designated Pech I, II, III, and IV. Located in the Dordogne region of France, these caves contain an archaeological record of intermittent Neanderthal occupation that spans from approximately 100,000 to 40,000 years ago. The deep layers of sediment on the cave floors have preserved a detailed history of Neanderthal life, particularly their methods for creating stone tools.
Pech I yielded the skull of a Neanderthal child in 1909, though many of its archaeological deposits were disturbed by early treasure hunters. Pech II and IV, excavated by archaeologist François Bordes in the mid-20th century, revealed long and detailed sequences of different stone tool industries. Pech IV is especially significant for its well-preserved hearths in the lowest layers, shows the controlled use of fire. The entire sequence records a timeline of technological changes against a backdrop of major climate shifts, from a temperate environment to a cold, glacial one.
Stone tools and chemical fire-starters
The primary tool industry identified at Pech de l'Azé is the Mousterian of Acheulean Tradition (MTA). This is confirmed by the discovery of a Neanderthal child's remains in direct association with these specific tools. The MTA is characterized by the production of flakes using the Levallois technique, alongside the creation of bifaces, or hand-axes. The site known as Pech IV also contains a unique stone tool assemblage found nowhere else, called the Asinipodian, which features an unusual mix of very large and very small flakes.
Beyond stone tools, the caves held a different kind of technological evidence: hundreds of small, black blocks of manganese dioxide. While initially thought to be pigments for body decoration, researchers now propose a more practical function. Experiments have shown that manganese dioxide powder, when sprinkled on wood, significantly lowers its auto-ignition temperature by more than 100°C. This suggests Neanderthals collected pigments but were actively engaged in a simple form of chemistry, gathering a specific mineral to make fire-starting easier.