The Transition in Indian Iron Technology With the Use of High‐Carbon Crucible Steel in the Mid‐1st Millennium bc

Studies of the role played by crucible steel in the evolution of early iron technology in India lag far behind its long‐standing reputation as a key historical material with unique functional properties. A comparative metallographic study found evidence of a crucible steel‐driven technological transition reflected in the numerous awl‐shaped iron objects from two archaeological sites in Maharashtra, India. Those in the first group were recovered from the early 1st millennium bc megalithic burials at Raipur, while the others were from the 2nd century bc settlement at Junnar. The former, products of bloomery iron fraught with nonmetallic inclusions, were forged into a desired shape and then carburized, if necessary, so that their carbon level ranged from zero to the eutectoid. In contrast, the latter contained few nonmetallic inclusions, and their carbon level was uniformly set at the eutectoid throughout the entire object. In addition, evidence of varying thermal treatments causing the formation of martensite, whether in its fresh or tempered state, was observed. We suggest that the shift evident in the foregoing results transpired gradually over centuries with the increased use of various high‐carbon steels until crucible‐based technology was a regular practice visible in archaeology.