Made up of 98% pure wrought iron and made about 400 A.D., it is 24 feet high, with 37 inches buried below the present floor level, and has a diameter of 16 inches at the bottom which tapers towards the upper end. The pillar was manufactured by forge welding. The temperatures required to form such a pillar by forge welding could only have been achieved by the combustion of coal. The pillar is a testament to the high level of skill achieved by ancient Indian blacksmiths in the extraction and processing of iron. A fence was erected around the pillar in 1997 in response to damage caused by visitors. There is a popular tradition that it was considered good luck if you could stand with your back to the pillar and make your hands meet behind it.