The Geological Survey of India (GSI) said it has identified commercially viable, diamond-rich kimberlite deposits covering 200 sq km in the Thimmasamudram district of Andhra Pradesh in southern India.

As per K Bhushan GSI deputy director general for the southern region, availability of diamonds and other lucrative mineral deposits have been explored in the south. He said the Thimmasamudram deposit contained an average grade of 65 carats per 100 tonnes (cpht), and added that 70 per cent of the initial sample consisted of gem quality stones. The largest stone found so far weighed 4.2 carats.

Meanwhile, GSI said it had also discovered platinum-related minerals in the Chitradurgah district in the state of Karnataka. The find could yield platinum or palladium in a ratio of up to 4 gm per tonne, according to the GSI.