A bizarre copper mask has South American archaeologists and historians baffled as to its origin and intended purpose. The mask was originally discovered in 2005 by residents of the village of La Quebrada in remote northwestern Argentina. Villagers there spotted a corner of the mask protruding from the ground after after a particularly heavy summer rain. When they dug the object out of the ground, they discovered it was a strange bronze mask which had been buried alongside human remains.
The mask was placed atop a pile of bones containing the remains of over a dozen different individuals. If researchers estimations are correct, the mask is about 3,000 years old, placing it among the oldest known metal objects in the Americas. The mask features four small holes near each edge, implying that it might have once been actually worn for some unknown ritual or symbolic purpose.
The mask is nearly square, measuring 7 inches long by 6 inches wide (18 x 15 cm), and is composed of over 99% pure copper, implying whoever made it had detailed knowledge of metallurgy. To forge such a mask, the metal would have had to have been heated, cooled, and reheated several times. According to the recently published study of the mask, the origins of such technological capabilities remain a mystery:
Despite many years of research, little is known about the roots of this ancient technology, as early evidence of copper metallurgy in the Central Andean region is rare. Although overlooked in the relevant literature, some crucial evidence points towards communities of the southern Andes—specifically north-west Argentina and northern Chile—as being among the precursors of this technology.
Gold objects have been found throughout the Andes dating back to almost 4,000 years, although researchers can’t be certain if they were produced locally or procured by some other means. The copper used to create this particular mask, however, was sourced locally. The find implies that metallurgy might have begun in more than once place in the Americas around the same time.