Archaeologists have unearthed a prehistoric cave in the Pyrenees containing unusual green mineral fragments and human remains, suggesting ancient copper mining and possibly burial rituals dating back 5,500 years.
The cave, situated over 7,300 feet above sea level, showcases evidence of repeated use over approximately 2,000 years, challenging previous assumptions about prehistoric peoples' limited engagement with high-altitude environments. The discovery of dozens of ancient hearths filled with crushed green mineral, potentially malachite, indicates early copper processing activities.
"For a long time, high-mountain environments were seen as marginal, places prehistoric communities passed through occasionally," explained Professor Carlos Tornero, lead author of the study published in Frontiers in Environmental Archaeology. "But we found a really rich archaeological sequence, including multiple combustion structures and a very large number of green mineral fragments."
The site, known as Cave 338, yielded 23 hearths within its deeper layers, with dates ranging from about 5,500 to 4,000 years ago. The presence of thermally altered mineral fragments, unlike other materials in the cave, strongly suggests deliberate processing by fire, rather than accidental burning.
Adding another layer of mystery, human remains including a child's finger bone and baby tooth were recovered from the same layer, sparking speculation that the cave might have served as a burial site. Other artifacts, such as pendants made from shell and a bear tooth, suggest connections with other communities and possibly symbolic significance tied to the local landscape.
Researchers are continuing their work to confirm the mineral's identity and origin, and future excavations aim to fully uncover the cave's history and the extent of its use by ancient peoples.
