Iron pillar of Delhi or Ashoka Pillar is 7 meters high structure in the Qutub Minar complex in Delhi, India. saiko3p – stock.adobe.com ...

Typically, iron and iron alloy structures exposed to the air or moisture oxidize over time, rendering them coated in rust unless they are protected, like the Eiffel Tower, by layers of special paint.

Qutub Minar is designated as a UNESCO World Heritage Site and is considered the tallest minaret in the world, attracting thousands of visitors every year. Heading 2 Image Credit: Pexels ...

Visitors to the courtyard of the complex’s Quwwat-ul-Islam Mosque will immediately spot an imposing 7.2-meter, six-ton iron pillar with a decorative top that’s even older than the complex.

New Delhi’s Iron Pillar has long fascinated scientists both at home and abroad. But it wasn’t until 2003 that experts cracked the metallurgical mystery behind this unusual attraction.