Dreadnought Resources (ASX:DRE) established an exploration target for the Stinger area at its Mangaroon critical metals project in Western Australia after an internal study identified economic potential, according to a Monday Australian bourse filing.

The conceptual target has been estimated at a tonnage range of 15 million tonnes to 60 million tonnes, with a 0.5% to 1% grade range of niobium pentoxide for 150,000 tonnes to 300,000 tonnes of contained niobium pentoxide.

Its shares fell 6% on market close on Monday.