Photo by Mohammad Najjar

Piles of rubble bestride the outline of a large square fortress and more than 100 smaller buildings at Khirbat en-Nahas in the Edomite lowlands of Jordan. The massive black mounds are slag, a waste product of the copper-smelting process, indicating that large-scale copper production occurred here at the time of the site’s occupation. Radiocarbon dating of the slag mounds shows that copper production took place here during the 12th–9th centuries B.C.E. and no later.