Four weighing stones made of basalt were unearthed between June 20 and July 3 during the sixth phase of excavation at the ancient archaeological site of Keezhadi on the banks of the Vaigai River in Tamil Nadu's Sivaganga district.

The discovery points to possible trading activity in this site, dating to between the sixth century BCE and first century CE, according to a senior official.

The spherical objects are black in colour with a flat base and polished surface, and all were made of basalt and weighed 300, 150, 18 and 8 grams respectively. Associated antiquities found along with these weighing stones are iron and copper objects.

"Charcoal was commonly found in all the levels (during the dig) and furnace was noticed at a depth of 0.61 metres, which shows traces of fire activity. All these findings indicate the possibility of the existence of trading activity in the industrial site of Keezhadi," R Sivanandam, Deputy Director of Tamil Nadu State Archaeology Department, said.

On June 20, a weighing stone was found at a depth of 1.53 metres from the north-west corner of the quadrant, weighing 18 grams. Its height was 20.74 mm and width 23.59 mm. Intense digging brought out the other stones at a depth of 1.22 m weighing 8 gram with 16.40 mm and 18.80 mm height and width respectively and a 300 gram stone at 1.45 m depth.

Associated antiquities found along with this weighing stone were iron, copper object and glass slag. Another stone weighing 150 gram was found at a depth of 1.50 metres, with 41.26 mm high and 47.11 mm wide. An iron object was also found along with it. 

In June, skeletal remains of a child were excavated from Konthagai, located about two kilometers away from Keezhadi. The sixth phase of excavations are taking place at Keeladi, Konthagai, Manalur and Agaram villages in Sivaganga district.

(With inputs from PTI)