A geophysical survey in Chhattisgarh's Mahasamund district identified five diamonds weighing 1.22 carats total.
The diamonds were recovered from 200 tonnes of bulk sample material at the Balod-Belmundi diamond block.
The exploration project is managed by a joint venture between NMDC and the Chhattisgarh Mineral Development Corporation.
Recovered stones include three gem-quality diamonds and two non-gem quality diamonds for industrial use.