As long as 220,000 years ago – far earlier than previously thought – people quarried rocks for their tools in places they specifically sought out. An international research team, including researchers from the University of Cologne, has demonstrated this behavior at the Jojosi site in South Africa, challenging the prevailing view that Paleolithic hunter-gatherers collected their raw materials incidentally during other activities. The study was published in the journal Nature Communications.
“At Jojosi, we found numerous traces of the quarrying of hornfels – a metamorphic shale – including blocks that were tested for their quality, flakes of various sizes, thousands of millimeter-sized pieces of production waste and hammerstones,” says Dr Manuel Will from the Department of Early Prehistory and Quaternary Ecology at the University of Tübingen. Hornfels is a fine-grained rock that was frequently used to produce tools in the Stone Age. “People worked cobbles on site here and knapped the material until they had achieved the desired shape from the rock – probably to make tools from it later.”
The researchers almost exclusively found ‘production waste’ here. The absence of both the end products and other traces of activity and settlement indicate that the people of the Stone Age were solely and deliberately visiting Jojosi to extract the coveted raw material. Remarkably, they were doing this for tens of thousands of years, at least until 110,000 BCE, as can be seen from the luminescence dating of the finds. Given its great age and long period of use, Jojosi adds new facets to the image of early Homo sapiens, indicating that they planned the long-term acquisition of resources much earlier than previously thought.
“Luminescence dating is a fantastic geochronological tool, as it tells us when sediment was last exposed to sunlight. We can apply this method over a wide age range, from a few years to multiple hundred-thousand years, which really helped us determining the age of the archaeological findings at Jojosi,” says Junior Professor Dr Svenja Riedesel from the Institute of Geography at the University of Cologne.
The Jojosi excavation site lies in vast grasslands in eastern South Africa, roughly 140 kilometres from the Indian Ocean coast. Geological processes during the Pleistocene formed a landscape characterized by erosional gullies, also exposing large hornfels layers. An interdisciplinary team headed by Manuel Will has been studying the geology and archeology of this landscape since 2022.
“On our very first visits, both on foot and using drones, we discovered about a dozen sites where perfectly-preserved, unweathered hornfels flakes were visible in eroded sediment – an absolute rarity for an open-air site,” says Will. During their excavations, the researchers uncovered clearly defined, stratified artefact horizons with high concentrations of 200,000 to two million finds per cubic metre. All sediment was sieved to retain even the smallest fragment.
Gunther Möller, PhD student at the Institute of Prehistory, Early History and Medieval Archaeology of the University of Tübingen, successfully assembled 353 of the left-behind pieces into ‘refits’. “With these 3D puzzles, we were able to see precisely where and how material was chipped off and in what order. Several of these puzzles together then allow us to draw conclusions about the form of the actual end product, before it was taken to another place,” explains Möller.
Media Contact:
Junior Professor Dr Svenja Riedesel
Institute of Geography
svenja.riedesel(at)uni-koeln(dot)de
+49 221 470 8834
Press and Communications Team:
Jan Voelkel
+49 221 470 2356
j.voelkel(at)verw.uni-koeln(dot)de
Publication:
http://doi.org/10.1038/s41467-026-70783-8