In 1899, an extremely well-preserved mummy from the sixth century A.D. was found at the well-known Chilean mining site, Chuquicamata. The mummy was determined to be a young indigenous miner who died in 550 A.D. ± 40 years. In the sixth century, the known technology used to produce copper metal from minerals must have been the reduction of copper oxides using charcoal with blown air. Minerals were abundantly available at Chuquicamata in 1899, and native copper could also be found. Their reduction using charcoal combustion must have required temperatures greater than those necessary for the copper oxides, copper carbonates, and native copper. This study shows that the miner could have melted copper metal by using sodium nitrate, which is abundant in local soil, to create an exothermic reaction in which combustion reached a temperature of more than 1,200°C.