Some 64% of the resource is now in the indicated category, with indicated resources increasing more than 100% to 28.2Mt grading 1.11% Li2O.

This resource update incorporates the results of 127 diamond core holes for 18,567m drilled during the phase five drill program with the increase in size coming from several areas including the north pit area where numerous laterally extensive pegmatite sills and inclined sheets were discovered.

This updated resource will be incorporated into the upcoming feasibility study which Piedmont expects to complete later this quarter for a 30,000 tonne per annum lithium hydroxide operation.

Shares in Piedmont last traded at A80.5c, valuing the company at $1.3 billion.