An ancient metal manufacturing unit has been unearthed at Porpanaikottai near here by a team of epigraphists and historians.

Located in the midst of hard and rugged laterite structures in the interior forest of Porpanaikottai, the unit testifies to the conventional method of boiling the ores using circular furnaces. A row of 14 furnaces can be seen at this site of which 11 are fairly bigger in diameter. Each furnace is separated by a distance of about five metres.

An oval-shaped cooling chamber has also been found in the area.

“Indications are that metal ores, after being heated to the melting point, should have been cooled at this chamber, as there is only chamber for the entire unit,” said A. Manikandan, founder of the Tholliyal Aaivu Kazhagam.

Accompanied by Karu. Rajendran, an epigraphist, he conducted a detailed study in the area to find that a few heavy stones, perhaps waste materials at the factory, had been found strewn all around the 40-acre site, believed to be 2,500 years old.