Minerals and Metals in Ancient India v1.c20.s3.t5.3

v1.c20.s3.t5.3

Both the specimens revealed laminated structure. Two sections were drawn from the blade and stem portion of the Komaranhalli spear measuring 178 cm in length and 3 cm in breadth. The blade showed a small metal core (the rest corroded) in three layers, two carburized and one uncarburized iron. While the light-coloured layer was ferritic and had low carbon (0.05%) and low hardness (HV 105), the darker carburized layer was of hypoeutectoid steel with dispersed pearlitic structure and had higher carbon content (0.2 to 0.24%) and higher microhardness. (HV 125-35) The section from the stem also revealed an air cooled dispersed pearlitic structure. Agrawal *et al.* (1990) concluded that the spear must have been prepared by hammering and welding together the sheets of carburized iron. The blade of the spear after receiving the final shaping at high temperature was also worked below the critical temperature 730°C and cooled in air. There is no evidence of hardening. The examination of other artefacts from Komaranhalli (1200-1100 BC) such as spearheads, daggers and swords also showed the evidence of lamination technique.