This is an actual thorough paper. The technique to how they did this low temperature cure is unknown to us. https://www.academia.edu/167025997/Prehistoric_artifacts_of_Mesoamerica_anthropological_evidence_of_ET_paleocontact Conclusion The multi-analytical investigation of the Aztlan collection, an assemblage of over 10,000 specimens from the southern highlands of Jalisco, Mexico, presents a significant challenge to traditionally established anthropological and archaeological timelines. The co...