Copper Workers' Experiments Might Have Helped Usher in Iron Age

Hematite mineral

CRANFIELD, ENGLAND—The development of iron metallurgy was one of the most pivotal moments in human history, as it allowed for the creation of stronger tools and weapons. Yet scholars have long debated about exactly how, when, and where this technological advancement took place. According to a statement released by Cranfield University, it may have been Bronze Age copper smelters who first helped spark the invention of iron. A team of university researchers reexamined materials that were originally found in the 1950s at the 3,000-year-old site of Kvemo Bolnisi in southern Georgia. Because of the abundance of hematite—an iron oxide mineral—and slag, the original excavators believed the site must have been an iron smelting site. The new research indicates that metallurgists at the site were instead producing copper, but they had been using iron oxide as a flux as part of a process to increase the resulting copper yield. Experts now believe that this experimentation may have been instrumental in the transition from the Bronze Age to the Iron Age. “That’s what makes this site at Kvemo Bolnisi so exciting,” said Cranfield University archaeological scientist Nathaniel Erb-Satullo. “It’s evidence of intentional use of iron in the copper smelting process. That shows that these metalworkers understood iron oxide as a separate material and experimented with its properties within the furnace." Read the original scholarly article about this research in Journal of Archaeological Science. To read about prosperous copper merchants on Cyprus, go to "In the Time of the Copper Kings."

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