Pyrenees Cave at 2,235 Meters Yields 23 Hearths and Burned Green Minerals, Reframing High Mountains as Sites of Prehistoric Industry
A cave high in the eastern Pyrenees held 23 hearths and over 170 burned green mineral fragments, suggesting repeated prehistoric visits tied to early copper processing rather than passing traffic.
Overview
Archaeologists excavating a cave high in the eastern Pyrenees have documented 23 hearths and more than 170 fragments of a burned green mineral, evidence that points to repeated prehistoric occupation linked to the early processing of copper. The site, known as Cave 338, lies at an altitude of 2,235 meters above sea level, according to the study published in Frontiers in Environmental Archaeology. The findings challenge a long-held assumption that high-mountain environments were marginal places that prehistoric communities only passed through occasionally.
The research, led by Prof Carlos Tornero of the Catalan Institute of Human Paleoecology and Social Evolution, was published in early May 2026.
What We Know
Excavation began over an area of six square meters at the front, or entrance, of the cave, the paper reports. Within that small footprint, the team documented a dense archaeological sequence. The Frontiers press release describes a total of 23 hearths, containing many crushed, burned green mineral fragments, a count also reported by ScienceDaily.
The green material is the most striking find. The paper states that over 170 chunks of rock fragments with patches of a predominantly green mineral were recovered by hand during the excavation. According to the same publication, it is proposed that they correspond to malachite, a copper carbonate, according to preliminary descriptions. Malachite is a copper-rich mineral that can be processed to produce copper, which is why the fragments matter for the story of early metallurgy. Tornero cautioned, however, that “The identification of the green mineral as malachite is still preliminary,” the press release notes.
What convinced the team the burning was intentional, rather than incidental, was the pattern of damage. “Many of these fragments are thermally altered, while other materials in the cave are not, which clearly suggests that fire played an important role in their processing and that there was a deliberate intention behind it,” said Dr Julia Montes-Landa of the University of Granada, a co-author, according to the Frontiers press release. “In other words, they weren’t burned by accident.” Smithsonian Magazine similarly reported that the thermally altered fragments suggest fire played an important role in their processing.
Radiocarbon dating spreads the cave’s use across thousands of years. The paper constrains the chronology of its main occupation phase, labelled NA 3, to an interval between 3,464 cal BC and 2,532 cal BC, and dates a later phase, NA 2, to roughly 1,109 to 908 cal BC. Earlier material at the site has been dated to between about 5,000 and 4,360 cal BC. ScienceDaily summarizes the overall pattern as people who repeatedly traveled to this remote location over a span of roughly 2,000 years.
The excavation also turned up human and ornamental remains. Researchers recovered a finger bone and a baby tooth belonging to at least one child, about 11 years old, in the cave’s main prehistoric layer. The team also found two personal ornaments. “We recovered two pendants: one made from a shell and another from a brown bear tooth,” said Tornero, as quoted by ScienceDaily. He added in the press release that they “come from prehistoric contexts, most likely around the second millennium BC,” noting that the shell pendant “has parallels in other sites in Catalonia, which suggests shared traditions or connections between different communities,” while “The bear tooth pendant is much less common,” according to Frontiers.
Why It Matters
The central claim of the work is a shift in how researchers read the high mountains. “For a long time, high-mountain environments were seen as marginal, places prehistoric communities passed through occasionally,” Tornero said, according to the press release. “But we found a really rich archaeological sequence, including multiple combustion structures and a very large number of green mineral fragments.” He described the use of the cave not as a one-off but as something recurring: occupations that, in his words, were “short to medium in duration, but happening again and again over long periods of time,” Frontiers reported.
What We Don’t Know
Several questions remain open. The malachite identification is still preliminary, and confirming it will determine whether the green fragments represent genuine evidence of copper sourcing or processing. The researchers also note they cannot yet say how long each visit lasted, inferring repeated, intermittent use from the density of remains rather than from direct evidence of continuous habitation, per the press release. And because only six square meters of the cave have been excavated so far, as the paper notes, the full extent of the site, including whether it holds prehistoric burials, has yet to be established.