In the heart of New Delhi, within the Qutb Minar complex, stands an iron pillar that has endured for 1,600 years. Despite being exposed to harsh sun and rain, the pillar remains unscathed at a towering height of 7.2 meters and weighing in at a massive 6 tons. The pillar can be found in the courtyard of the Quwwat-ul-Islam mosque in Mehrauli district’s southern part.
The durability of this ancient structure has puzzled scientists for years. Typically, iron constructions rust when exposed to air or moisture over time. However, the pillar has remained intact thanks to a unique construction technique called “forge welding,” which was used in ancient India. This method involved combining wrought iron with high levels of phosphorus while excluding sulfur and magnesium.
The presence of a thin layer of misawite on the surface of the pillar also contributed to its longevity. As a result, the iron pillar has become a symbol of ancient Indian craftsmanship and metallurgy, showcasing the country’s ability to produce iron in those times.
Despite its mysterious origins and missing statue of Garuda, Lord Vishnu’s mount, the iron pillar continues to fascinate archaeologists and scientists alike. To preserve this historical treasure, the Archaeological Survey of India constructed a moat around it in an effort to minimize human impact and ensure its continued protection.