A view of iron and steel making technology in the Yan region during the Warring States period and the Han dynasty: scientific study of iron objects excavated from Dongheishan site, Hebei province, China

Iron objects excavated from the Dongheishan site provided a chance to systematically study the iron and steel making technology during the Warring States period and the Han dynasty in the Yan region, north China. According to the results of radiocarbon dating, metallographic and slag inclusions analysis, it was found that they were made of cast iron or cast iron subsequently processed into steel, and most radiocarbon dates of iron artefacts were consistent with the determination from their archaeological context. The technology in this region was as advanced as the Central Plain China, and it was probably a previously unknown centre of technological innovation during this period. Meanwhile, the results showed that the local craftsmen used different types of iron and steel and different technologies to produce different types of objects.