Wind Furnaces of the Atacama Salt Flat, Northern Chile: Copper Extractive Metallurgy at the Edge of Qhapaq Ñan

An archaeological investigation at the western margin of the Cordillera de la Sal Formation in Catarpe (San Pedro de Atacama, northern Chile), revealed a series of pyrometallurgical furnaces from the Late period (AD 1400–1536). The furnaces, found at the Catarpe Túnel archaeological site, were used to reduce atacamite, clinoatacamite, brochantite, chrysocolla, and azurite to obtain unalloyed copper prills. Exceptional for the Atacama oasis and salt flats, Catarpe Túnel represents the only major archaeometallurgical site recorded in the area. Archaeometric analysis has determined the type of ore smelted, the composition of the metallic copper produced, and the characteristics of the fuel used by the operations. Although these operations are typical of the local metallurgical tradition, their proximity to a documented section of the Qhapaq Ñan and the Inka administrative center of Catarpe Este led us to wonder about the possible Tawantinsuyu influence in the region.