The 55 square kilometre Mt Thirsty Cobalt-Nickel-Manganese Project is located 20 kilometres north-northwest of Norseman, Western Australia. The deposit differs significantly from typical WA nickel laterite occurrences in that is completely oxidised containing mainly goethite, haematite and manganese oxide minerals with very low clay content. This makes the deposit very amenable to cheaper atmospheric leaching techniques which don't require expensive and problematic autoclaves.

Due to the intense oxidation of the ores, mining is extremely low cost as the ores can be extracted without the need for blasting. The majority of this soft ore is shallow and flat lying occurring only 10-15m below surface. Another advantage to the deposit is the location of the high grade ore zones. They are situated closest to the surface allowing the deposit to be high graded during the first 3-4 years of production, dramatically reducing capital payback.

Metallurgical testing and pre-feasibility work in conjunction with MTJV partner Fission Energy Limited has highlighted the potential world class nature of this outstanding project. The Mt Thirsty Project has the potential to emerge as the world’s fourth largest cobalt supplier with capacity to deliver 3,700 tonnes of cobalt, 10,300 tonnes of nickel and 27,000 tonnes of manganese per annum during the first 3 years of production. Cash costs have been estimated at between A$80-A$100 per tonne, equivalent to US$2.49 per pound of nickel after cobalt credits making the Mt Thirsty Project one of the lowest cost atmospheric leaching operations in the world.

Earlier this year the MTJV set out to explore the Mt Thirsty area for a potential primary sulphide source to the world class Cobalt- Nickel-Manganese Oxide Deposit. After completing surface mapping and focussed geophysical surveys over priority areas at Mt Thirsty, the first ever diamond hole (MTDD008) searching for nickel sulphide mineralisation in the area was drilled to test a large electromagnetic (“EM”) anomaly uncovered by the geophysical surveying.

MTDD008 was successful in identifying primary nickel sulphides beneath the Mt Thirsty Cobalt-Nickel-Manganese Oxide Deposit, intersecting anomalous zones of disseminated and stringer nickel sulphide mineralisation. However, the most exciting discovery was a small 6 centimetre thick stringer of massive nickel sulphides within a much younger Proterozoic dyke. It’s thought the dyke has thrust its way up from great depths through massive nickel sulphides on the basal footwall contact dragging up fragments of nickel ore on its way to the surface. It has been the long held belief of the MTJV that the high grade Cobalt-Nickel-Manganese Oxide Deposit may have formed from a primary nickel-cobalt sulphide source nearby. It is possible that extensive massive nickel-cobalt sulphides deposited on the basal footwall contact beneath Mt Thirsty are indeed that source.

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