Iron artefacts used at an ancient jade mine in the Hexi Corridor: a technical observation

Abstract

This paper presents a study of 45 iron objects unearthed from the ancient Jingbao’er jade mining site in the western Hexi Corridor, dating from the Warring States period to the early West Han dynasty (about fourth–first centuries BCE). Metallographic and slag inclusion analyses were conducted to investigate the material features and their potential correlation with intended applications. Of the analysed items, 38 were made of cast iron, some of which had been decarburized or graphitized through annealing treatment to enhance their properties. Seven artefacts were identified as bloomery iron, indicating a distinct iron production tradition, likely localized and small in scale. It is conveyed that by the late first millennium BCE, the supply of iron artefacts at the Jingbao’er site was predominantly derived from the cast-iron system, with evidence of regional bloomery smelting highlighting the complexity of iron production during this period. These observations offer new insights into the adoption of iron in the Hexi Corridor and the dynamics of regional technological exchange.