The Iron Pillar of Delhi is a 7-meter tall structure that is a testament to the advanced metallurgical skills of ancient Indian blacksmiths. Erected during the reign of Chandragupta II, the pillar is made of 98% wrought iron and has stood in the open air for over 1,600 years without rusting. This resistance to corrosion is due to a high phosphorus content in the iron and the formation of a protective 'misawite' layer on the surface, a result of the specific smelting techniques used at the time. The pillar carries a Sanskrit inscription in the Brahmi script, which serves as a historical record of the king's victories. Its existence challenges the long-held Western notion that advanced ironworking was a modern European development, as the pillar's mass and purity were not achieved in Europe until many centuries later.