An ironsmith created an iron pillar beside the Qutub Minar in Mehrauli, Delhi.
The pillar is still safe and weathered after decades.
This proves that our ancestors invented a rust-prevention technology.
It possesses an iron oxide layer on its surface, according to studies.
They had mixed phosphorus at the time of its genesis.
It had been exposed to extreme heat and had been painted with a variety of materials.
Final answer:
Hence, the iron pillar of Mehrauli, Delhi, known as the magic pillar, is not yet rusted due to the iron oxide layer on its surface, which was mingled with phosphorus.