BIG BUSINESS. In the early Iron Age (1200–900 B.C.E.), copper production reached its peak and became heavily industrialized. The ore was brought from the mines to copper-production centers such as Khirbat en-Nahas (“Ruins of Copper”), where it would be smelted and then traded abroad in ingots. Over a hundred buildings at Khirbat en-Nahas were used for copper production. In this four-room workhouse, excavators found more than 350 grinding and pounding tools used to extract ore from the bedrock.