Bronze Age Copper Smelting Likely Produced Iron as Unintended Byproduct

A new study by Robert Downes of the University of Oxford suggests that Bronze Age metalworkers in the Near East inadvertently produced significant quantities of iron while smelting copper. Through full-scale furnace experiments replicating ancient conditions, Downes demonstrated that iron consistently entered copper metal from ore charges. Although casting processes removed over 70 percent of this iron, explaining its scarcity in ancient copper artifacts, the remaining visible iron phases would have been noticeable to workers at high concentrations. The research estimates that sites like Timna and Wadi Nasib generated hundreds of tonnes of unintended iron over centuries. Downes argues that while direct extraction of usable iron from copper smelts was impossible due to entanglement, repeated observation of these byproducts likely prompted metalworkers to experiment with iron-bearing minerals alone. This gradual trial-and-error process eventually led to the mastery of bloomery iron smelting and forge welding techniques. These developments laid the technological foundation for the widespread adoption of iron metallurgy across the Near East by the early 1st millennium BC, reshaping historical understanding of the transition from the Bronze to the Iron Age.