- Where in the world was zinc smelted for the first time?
- Which agency conducted the first study of Zawar mines?
- What things were found at Zawar?
- To whom goes the credit of distilling zinc?
- Why did Zawar prosper?
Zawar located on the bank of Tiri river, about 38 km south of Udaipur town in the Aravalli hills in Rajasthan, has the distinction of being the first in the whole world in smelting zinc through distillation technology. It is the only known ancient zinc smelting site in India. It is considered to be the beginning of Industrial Revolution in the World. The entire valley of Tiri at Zawar is marked by huge heaps of slags and retorts that indicate a long tradition of zinc smelting at Zawar. On some slag-mounds are found remains of houses made of used retorts and stones perhaps belonging to the smiths.
The archeometallurgical activity at Zawar was casually recorded by several Indian and British scholars between 17th and 19th century. However, the immense remains were highlighted between 1982 and 1990. Perhaps encouraged by these reports of British Museum, M.S. Baroda University initiated a study at Zawar jointly with Hindustan Zinc Ltd., Udaipur in 1983. This team carried out extensive investigations both for ancient mining as well as smelting of zinc at Zawar and discovered incredible evidence of mining, furnaces used for zinc smelting besides primitive smelting retorts from the dam fill of Zawar.
Zinc ores are widely distributed in the country but major deposits are found in the Aravallis. The mineralized belt of Zawar extends for about 25 km. Some other minerals that are distinct and could be separated manually were also found. This explains why zinc mining and smelting developed only at Zawar.
The entire valley of Tiri river in Zawar is dotted by massive dumping of slag and earthen retorts, indicating a long tradition of commercial production of zinc. Several radiocarbon dates bracketed between 12th and 18th century also confirm this activity. It appears that the main expansion of the industrial phase of zinc production began at Zawar sometimes between 11th and 12th century.
At Zawarmala a bank of seven distillation furnaces roughly squarish in shape were discovered. Each furnace had two chambers, upper and lower one separated by a thick perforated plate of clay. It is presumed by the excavators that the furnaces may have looked like truncated pyramids. Brinjal shaped earthen retorts filled with charge were placed on the perforated plate in inverted position in the upper chamber. As many as 26 retorts were placed in each furnace for smelting and they were heated for three to five hours. The retorts were made in two parts and joined together after filling the charge. To prepare the charge the ore was crushed and ground and mixed with organic material and cow dung, rolled into tiny balls and left in the sun for drying. Then the balls were placed in the retorts. A thin wooden stick was placed in the narrow opening of retort which perhaps prevented falling of charge in the lower chamber before heating when they were initially inverted in the furnace and at the same time would facilitate the escape of zinc vapor formed during heating. The different sizes of retorts indicate the use of different size and shape of the furnaces. After heating, zinc vapor was collected and condensed in the lower chamber in small earthen pots. It was surely an indigenous method that was derived for downwards distillation of zinc vapour. It was for the first time anywhere in the world that pure zinc was produced by distillation process on a commercial basis. It is possibly the ancestor of all the high temperature pyrotechnical industries in the world.
The credit of innovating special retorts and furnace for distillation of zinc surely goes to the Bhil tribe of southern Rajasthan. These Bhils have been distilling alcohol since millennia. It was surely this local knowledge they could successfully employ for distillation of zinc.
It is interesting to note that both Charak Samhita and Susruta Samhita refer to ‘pushpanjan’, that was prepared by heating a metal in air and was used for curing eyes and wounds. This could be identified as zinc oxide as no other metal would reacts in the air to produce an oxide suitable for medicinal purposes. Therefore, these Ayurvedic texts are perhaps the earliest literary evidence of zinc in India.
Due to the huge quantity of zinc production, the annual income from Zawar was quite handsome. It is likely that the revenue earned due to brisk trade of zinc at Zawar was utilized for construction of the large monuments, existing forts, huge water reservoirs, temple complexes, water structures etc. in Mewar.
There are a few brass cannons at Udaipur also which might have been made by zinc obtained from Zawar.
Content Courtesy: Dr. J.L. Kharagwal