When was the Iron Age?
Iron Age
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In China, Chinese bronze inscriptions are found around 1200BC, preceding the development of iron metallurgy, which was known by the 9th century BC,[37][38]   Therefore in China prehistory had given way to history periodized by ruling dynasties by the start of iron use, so "Iron Age" is not typically used as to describe a period in Chinese history.  Iron metallurgy reached the Yangzi Valley toward the end of the 6th century BC.[39] The few objects were found at Changsha and Nanjing. The mortuary evidence suggests that the initial use of iron in Lingnan belongs to the mid-to-late Warring States period (from about 350 BC). Important non-precious husi style metal finds include Iron tools found at the tomb at Guwei-cun of the 4th century BC.[40]