The Delhi Iron Pillar and its iron

Physical characteristic and historical background of the Delhi Iron Pillar are review. Discussing the chemical, spectrochemical and X-ray diffraction analyses of the metal and rust scrapings obtained from the pillar the author compares these results with the data relating to other ancient iron parts particularly the beams of Konark Temple. Absence of Manganese is a common factor in all these irons which also show great similarity in their other properties. After a critical study of the theories formed so far the author concludes that the pillar has been constructed by forge welding small pieces of iron made in primitive furnaces and attributes its anti-corrosive properties to the absence of manganese on one hand and the high phosphorus of the iron on the other. (M.K. Ghosh, former Senior Chemist, Research and Control Laboratory, TISCO, Jamshedpur)