Cave-divers have discovered a red-ochre mine in a cave system on Mexico’s Yucatan peninsula – and learnt that it was worked between 12,000 and 10,000 years ago, making it the oldest-known such mine in the Americas.
The system of cenotes and underwater passages in Quintana Roo lies 5-6 miles from the Caribbean coast, though its exact location is being kept secret. It was found three years ago but the research team have only now released their study of the previously unsuspected prehistoric mine, preserved just as it was left by the last miners.
Red ochre has been the most commonly identified inorganic paint used through history worldwide. No evidence of how the early miners used it is thought likely to survive at the site, but they could have valued it as a medium for rock-painting or body decoration, tanning animal skins or, with its high arsenic content, as an insect repellant.
Ten skeletons dating back to the same Pleistocene-Holocene period have been found to date in Quintana Roo’s flooded cave systems, and experts had until now supposed that the people had sought water or shelter in the then-dry caves. Now it seems that these early explorers had another reason to head underground.
The “La Mina” site was discovered by cave-divers Sam Meacham and Fred Devos from CINDAQ (Research Centre of the Quintana Roo Aquifer System), later joined by Eduard Reinhardt from McMaster University in Canada. Underwater archaeologists from INAH (Mexico’s National Institute of Anthropology & History) joined the team to continue the investigations.
La Mina, a 900m series of underwater passages in places no more than 70cm across, was found in one of the system’s three caves, Sagitario.
There Meacham and Devos noticed that many of the stalactites and stalagmites had been broken in half, while stones had been deliberately stacked in small triangular piles. There were also heaps of coal on the floor, soot marks on the ceiling and carved-out cavities on the ground containing traces of what turned out to be ochre.