Powder Metallurgy in Tribal India?

By Udit Chaudhuri

One usually associates powder metallurgy with space-age industry. Very few know that the wall-mounted oil-lamp-cum-key-stand and the slender-limbed animal figurines that you see in Indian Handicrafts displays, are products of a purely ingenious technology evolved by the Muria tribes around the Chhattisgarh region, centuries ago.

Wrought-iron figures are a popular sight in handicrafts shows. Their original inspiration comes from the Muria tribe inhabited mostly around the erstwhile Bastar State, spread partly over Chhattisgarh and Odisha. That region is also home to the more popular Dhokra or bell-metal investment-cast sculpture, but that’s another story. Sheer ingenuity hallmarks the process of the Muria Lohar or iron-monger.

While conventional geology and metallurgy elaborate the scientific selection of ores of a suitable grade, to dress or enrich and extract metals from, the Muria Lohar uses a native look-n-feel instinct refined over generations, to estimate iron content in boulders among the abundant haematite-bearing formations in this region. To smelt the ore, he breaks each boulder with a sledge hammer into chips. Likewise, he pulverises coal and compacts balls of dampened ore mixed with coal in a ratio he sees fit.

The Muria Lohar’s furnace is as ingenious. Smelting requires a reducing flame. So there is a pit filled with coal and topped with the ore-coal balls, blown from below by an animal hide. The skin of the forelimbs provides a pair of ducts while the trunk serves as air trap. A bamboo strip acts as a spring to pull the trunk outward to draw air via a flap. The Lohar, often substituted by a family member and supported by the spring, uses each foot to close an orifice and compress air one step at a time, so that it blows continuously.

Kindling like charcoal starts the combustion. As blow-heating continues, one sees a perfect blue flame while the ore-coal balls glow bright red. The Lohar uses a pair of tongs to pick up a ball and hammers it into a sheet, using a chisel to cut profiles, occasionally using the furnace to re-temper the work-piece or anneal if needed. This way, he forges the arched frame, typical of these forms, often with saw-tooth or bevelled edges. A rock platform serves as anvil.

Next, he twists cut-out parts of the same sheet and forges these into intricate and graceful shapes like the slender-limbed animal and bird forms, gracefully posing inside these frames, sharing a home with the oil lamps in an integral assembly. Beating a number of balls together make a larger figure if needed. Stand-alone sculptures of locally inhabiting animals like lions, monkeys and deer are also made by this technique. What a pity such talent was never tapped by our aviation or auto industry!

A typical product is the popular ‘bird frame’ as shown in the picture here. This is in fact an object of worship. This wrought iron is very close to carbon-steel in its properties and does not require any weather-protective coating. However, unfortunately, the Muria Lohar is a dying breed and ‘fake folk’ products made of scrap steel and coarse shapes flood our handicrafts fairs and emporia. A genuine Muria wrought-iron artefact is as treasured as jewellery.