Centuries later it was built, two metallurgists from Pune have come up with the first-ever estimate of the pillar’s weight. It’s 6,511 kg — the decorative bell weighs 646 kg while the weight of the main pillar is 5,865 kg.

The metallurgists deduced the weight using a computer software.

“This is the first phase of the research. We plan to go further and figure out details on the stresses and stability of the pillar as well as the manufacturing technology used,” said P P Deshpande who was with the department of mechanical engineering at the Sinhgad Institute of Technology when he carried out the study last year. He is with the College of Engineering Pune (COEP) at present.

According to Deshpande, the overall findings would be of considerable significance as it could help in modern day manufacturing and designing techniques. “The pillar is more than 1,600 years old, yet the corrosion is very low because of the phosphorous content. Also, it’s made by forge welding. All these revelations can greatly help our present designing and metallurgy skills,” he said.

Along with Deshpande, A P Kulkarni of Pune’s Vishwakarma Institute of Technology was involved in the concept and execution of the project. The researchers used the available dimensions of the pillar to simulate its computer image using feature-based modelling software — CATIA V5R16.

“It took us about 20 days to model its shape and structure. The top part, the bell shape, was particularly difficult to model. This is for the first time that this improved technology has been used for archaeological work in India,” said Kulkarni, expressing hope that computer modelling studies will be extended to understand the composition, weight and forging of other such historical objects like cannons.

Deshpande said they were inspired by the work done by Dr R Balasubramaniam of IIT Kanpur on the iron pillar, which made them choose it as the object of their attention.

Balasubramaniam, who has written many papers on the pillar, described the study by the two Pune metallurgists as “significant and commendable”.