Metallurgy in pre-Columbian America

Metallurgy in pre-Columbian America is the extraction, purification and alloying of metals and metal crafting by Indigenous peoples of the Americas prior to European contact in the late 15th century. Indigenous Americans had been using native metals from ancient times, with gold artifacts from the Andean region being dated to 2155–1936 BC, and North American copper artifacts being dated to approximately 5000 BC. The metal would have been found in nature without the need for smelting, and shaped into the desired form using hot and cold hammering without significant chemical changes or alloy formation.

Source: Wikipedia — Metallurgy in pre-Columbian America (CC BY-SA 4.0)