Arafura Resources has announced a substantial upgrade in Joint Ore Reserves Committee (JORC) mineral resources at its Nolan's Bore Rare Earths deposit, prompting a rise in confidence for its Whyalla Rare Earths Processing complex.

Total mineral resources at Nolan's Bore are now estimated at 46 million tonnes.

This represents a 52 per cent increase in total resources on the November 2008 estimate of 30.3 million tonnes.

In-situ resources of Rare Earths, phosphate and uranium are also shown in total in-situ identified resources of rare earths, phosphate and uranium and Nolans Bore has been expanded by 36 per cent, 30 per cent and 43 per cent respectively since the November 2008 resource estimate.

The new resource model incorporates the results of all drilling and costeaning activity undertaken by Arafura at Nolans Bore since 2000.

It follows a comprehensive resource expansion drilling campaign which was completed in 2011.

Arafura Resources general manager of exploration and development Richard Brescianini said the Nolans project resource base had been upgraded in excess of 50 per cent from previous 2008 estimations, with the contained rare earths increasing by 36 per cent.