PERTH (miningweekly.com) – Potash developer South Boulder Mines has reported a maiden Joint Ore Reserves Committee-compliant reserve of 1.1-billion tonnes, grading 10% potassium oxide, for 205-million tonnes sulphate of potash at its Colluli project, in Eritrea.
Some 287-million tonnes of the reserve was classified as proven, with a further 820-million tonnes classified as probable.
South Boulder MD Paul Donaldson said on Tuesday that the maiden reserve was an outstanding result for Colluli and reaffirmed the significance of the project’s resource.
“The shallow mineralisation of the potassium-bearing salts in combination with highly favourable ambient conditions, allows opencut mining of the resource, giving high resource recovery.”
Donaldson noted that the large mineral resource and associated reserve estimate allowed the project substantial growth and product diversification over time.
“Once the definitive feasibility study for the two phase production of sulphate of potassium has been completed, work will commence on the logical pipeline of projects that will grow the project to its full potential.”
A March prefeasibility study into the Colluli project estimated that it would require a capital investment of around $442-million. The study examined a two-module development with an expected production of 425 000 t/y sulphate of potash for the first five years of operation, increasing to 850 000 t/y for the remainder of the proposed 30-year mine life.
First production was slated to start in 2018.