The Indian town keeping ancient technique of lost Chola bronze casting alive

Located 35km from Thanjavur in India is Swamimalai, a remote town of casting, where skilled artisans breathe life into Chola bronzes, also known as panchaloha idols, as they've done for thousands of years.

The majority of Chola bronze statues exhibited in museums worldwide were made between the 7th to 14th centuries in southern India. However, in the present day, the ancient technique of Chola lost wax casting is exclusively practised in Swamimalai.

In a display of divine artistry in one such foundry, a rusty bronze statue of Siddhi Buddhi Ganesha sits in a small pool of water. Numerous other oxidised statues of Hindu deities – completed masterpieces and works-in-progress of Radha Krishna, Vishnu poised on a lotus and lord Shiva clad in his Ardhanarishvara avatar as Nataraja – are scattered over the courtyard.

“We make one mould for one piece using the Chola lost wax process, thus every piece is unique. Even the smallest idol and also the large pieces are made of a single cast,” Suresh Rajan, general manager of Rajan Industries, tells The National.

“This is the speciality of this work. This tradition dates back more than 1,000 years when Chola kings supported the artists, and we still employ the same technique even now. We don't use any machinery, no electricity and no pollution. It is completely eco-friendly.”

Sculptors use beeswax to fashion intricate designs, which are subsequently enveloped in clay, dried and repeatedly coated until the final result resembles a solid mass of earth.

“This type of Chola bronze is used for temples and decorative items. The clay we use is a particularly rare clay obtained from the Cauvery river. Because this is the last section of the river, there is naturally some salt present, making it ideal for this craft,” says Suresh.

Prabhakar, a senior artist, explains the first stage of the wax modelling. He uses his fingers to shape a sample figure out of a pliable mixture of 50 per cent honey beeswax and 50 per cent resin derived from a gum tree, gauging the measurements with a coconut leaf strand. “Beeswax is very soft, we cannot make any shape out of it. Resin helps balance that. By combining these two, the mould hardens within a fraction of seconds,” he says.

In another corner, an artist named Manikhandan delicately cradles a wax sculpture, its protruding edges serving as a canvas for a symphony of light. Legs crossed and his back bent over a sturdy bench, he is immersed in the task at hand and chips away at the sculpture before him. “During the Chola dynasty, these bronze deities were dubbed 'utsava murtis',” says Manikhandan.

Explaining what happens when clay is applied as the second layer, he adds: “It is the hard layer. Then, we dry the cast in the sunlight,” he says. “After that, we rotate the mould, apply wax and sundry it again. We heat the mould in the slanting position. The wax should be lost here to obtain the negative hollow inside the mould. So we call it the lost wax process.

“After we receive the negative impression, we heat the mould to 1,300ºC and the metal to 1,500ºC before pouring the mixture into the cast. Copper accounts for 84 per cent, zinc for 14 per cent and tin accounts for two per cent, whereas gold and silver are only used for temple purposes. We break the mould after it has cooled.”

The portable mini-furnace beside Manikhandan burns bright, as another artist feeds the fire. The object is inserted into a kiln for baking and as it heats up and melts, the liquefied wax drains out through a hole at the base. Following this, a blend of five metals (panchaloha) is poured into the resulting cavity.

Once the mixture has solidified, the mould itself is shattered and the illustration is finished and polished. Giving the wax model further detailing, it is passed on to another sculptor, who designs a clay mould out of vandal mun – a type of soil taken from the banks of the Kaveri river – and uses sand to encase and dry the statuette in the sun for a week.

The cast is then placed into an earthen oven with firewood and dried cow-dung patties and baked until the wax once again melts away. Inside as the wax-free mould, known in Tamil as karuvu, cools down, it is broken and cast out – leaving a raw statuette, which is chiselled and filed down, before finally being polished during the final stage.

The process doesn't end here. The idol's eyes are sealed very carefully with a combination of honey and ghee, and then reopened by a Vedic ritualist with a golden needle adorned with a diamond.

The handcrafted religious designs are based on the Shilpa Shastra, an ancient treatise that defines particular standards for sculpture and Hindu iconography. Shilpa Shastra contains precise measurements in the form of a dhyana slokam hymn. Other details, such as the size of the crown and platform, are left up to each sculptor.

“One cannot learn all these techniques in a crash course,” says Rajan. “This lost wax technique takes at least five to seven years to master, sometimes even longer.”