IIT Madras’ ‘synthetic clay’ saves Bidri craftsmen from losing their trade

CHENNAI: ‘Bidriware’, the craftsmanship unique to Bidar in Karnataka, is made from a special clay-sand drawn from the Bidar fort. from where it gets its name. After the Archaeological Survey of India (ASI) recently declared the Bidar fort a ‘heritage site’, the artisans nearly lost their trade. But thanks to a

synthetic clay

that has been cooking in the labs of IIT-Madras here, it appears the

Bidri

can shine on.

The prohibition on procuring sand from Bidar area matters, because the artisans have long held that this clay sand is what gives the Bidri metal (Zinc copper alloy) its distinct black-silver colour. This would mean the entire community of artisans dependent on bidri-crafting as a trade would vanish. So after an NGO ‘Sahayog’ approached IIT-M’s Rural Technology Action Group (RuTag) with the problem, a research team has been researching how to reproduce a type of sand which when treated with the alloy can produce the same color. “While the traditional belief is that the fort area has a ‘special’ sand exclusive to the community in Bidar, we got down to understanding what the special component in this sand is. It has been found to be a nitrogenous compound,” says Abhijit P Deshpande, head of RuTag and professor in the Chemical Engineering department.

The traditional craftsmanship style involves the alloy being treated in the clay sand along with aluminium chloride after which the surface is coated with black patina (oxide) to get the black-silver sheen. Now, the process will be reproduced with the sand that has been treated by the lab process, which has cost the university about Rs 2lakh in research. This has been done by the joint efforts of two assistant professors at the

Department of Metallurgical

and Materials engineering — Lakshman Neelakantan and Manav Mukherjee .

It is also being coordinated at a government level by the Office of Development Commissioner - Handicrafts Dharwad (Karnataka) and Sahayog, which works with the artisans.