Archaeomagnetic evidence indicates post-Inka reheating of metallurgical kilns at Quillay (NW Argentina)

This study presents an archaeomagnetic analysis of five metallurgical kilns from the settlement of Quillay (Catamarca, NW Argentina), attributed to the Inka period on the basis of radiocarbon dates and archaeological evidence. All five structures yielded consistent paleofield values, and directional and intensity determinations are statistically ndistinguishable which suggests that the sampled parts of the kilns were reheated within a relatively short interval. Comparison with geomagnetic field models, particularly BIGMUDI4k.1, indicates that this last heating event occurred between the late nineteenth and mid-twentieth centuries, rather than during the Inka occupation. The discrepancy between the archaeomagnetic and radiocarbon evidence is therefore consistent with a later remagnetization event affecting the structures. Possible explanations include a local wildfire or the deliberate re-use of the upper chambers to recover copper from slag. The results refine our knowledge about the occupational history of Quillay, and support the interpretation of a later thermal event affecting structures originally used in Inka times.

The kiln during archaeomagnetic sampling; (B) Sketch reconstruction in pseudo-cross-section, depicting the upper chamber with vents on the floor and the tunnel that connected it with the lower chamber (not drawn); (C) Cross section of two archaeomagnetic samples photographed during laboratory sub-sampling prior to demagnetization. Lines indicate different facies: note the color variation with width, with darker zones corresponding to the innermost centimeters of the kiln’s wall

del Río J, Gómez-Paccard M, Palencia-Ortas A, Chauvin A, Basile M, Ratto N, et al. (2026) Archaeomagnetic evidence indicates post-Inka reheating of metallurgical kilns at Quillay (NW Argentina). PLoS One 21(5): e0350160. https://doi.org/10.1371/journal.pone.0350160