Police said that "Gel-90" and "Radial Power 90", which are common explosives and 6,400 metres of wires and 217 metres of fuse wires were found in the 5x5x5 pit on the premises of K G Granite company at Thiruvathavur.
The explosives and other items was covered by stacks of tyres, they said.
Officials had on August 29 sealed three godowns of two granite companies after detecting large quantity of explosive materials allegedly stocked without license and disregarding safety norms.
Meanwhile, Tamil Nadu Pollution Control Board has issued a notice to the PRP Exports for allegedly disposing their effluents and granite wastes from polishing units into nearby tanks and sought an explanation from the company, among those facing charges of illegal quarrying.
The crackdown on the granite firms was launched in the backdrop of a recent report by former district collector U Sagayam pegging loss due to illegal quarrying of the blue metal in the region at over Rs 16,000 crore.
Several persons, including Durai Dayanidhi, son of Union Minister M K Alagiri, have been booked for alleged illegal sand and granite mining by companies owned by them.
