OZ, Cassini Formalize West Musgrave Joint Venture

OZ Minerals has signed a joint-venture earn-in agreement with Cassini Resources that allows OZ to earn up to a 70% interest in the West Musgrave copper-nickel project in a remote area of east-central West Australia. Initial work will focus on an A$3 million scoping study to identify a commercial pathway to begin mining the Nebo-Babel deposits on the project, currently Australia’s largest undeveloped copper-nickel resource.

OZ will begin a diamond core-drilling program in November to collect new samples for metallurgical studies to recover copper and nickel from the Nebo-Babel deposits. (Photo: OZ Minerals)

The initial study will set out both the appropriate size of any future mine and optimal infrastructure solutions to support the project. The study is scheduled for completion in September 2017.

The West Musgrave earn-in agreement is structured in three phases. After the initial scoping study, OZ may earn a 51% interest in the project by sole funding an additional A$15 million within 18 months toward completion of a prefeasibility study and the start of a definitive feasibility study (DFS), as well as sole-funding at least A$4 million for regional exploration over the same 18-month period.

Following this 18-month period, OZ may earn an additional 19% interest, for a total 70% interest, by sole funding a further A$10 million within a 12-month period toward completion of the DFS and a further A$4 million on regional exploration.

An extensive regional exploration database will enable targets to be rapidly assessed and tested.

As part of the geometallurgical modeling, work will begin in November on a 700-meter (m) PQ diamond core-drilling program to collect new samples for further metallurgical test work aimed at improving recoveries of both copper and nickel from the Nebo-Babel deposits. A reverse-circulation drilling program will also be undertaken of potential high-grade extensions to the already estimated 200 million metric tons (mt) of ore at greater than 1.3% copper equivalent.

The West Musgrave project includes the Nebo-Babel copper-nickel sulphide deposits and the Succoth copper deposit. The Nebo-Babel deposits lie with 50 m of the surface and are flat, shallow-dipping ore bodies, with the higher-grade mineralization occurring at the top.

Since 2000, the deposits have been subject to an estimated A$100 million in exploration studies, including more than 75,000 m of drilling in 307 drill holes; metallurgical test work; and environmental and scoping studies.

Commissioning Commences at Nova Nickel-copper Project

Independence Group began commissioning the processing plant at its 100% owned Nova nickel-copper project in southern Western Australia in mid-October, approximately four weeks ahead of schedule. Construction was completed on October 10, and crushing and milling of ore began on October 14.

In the Nova underground mine, approximately 8 kilometers (km) of development had been completed as of mid-October, and some 85,000 mt of ore at an average grade of 1.5% nickel and 0.7% copper had been mined from development and stockpiled on the run-of-mine stockpile. Mining of the first stope began in September in an area defined by grade-control drilling and outside of the current mineral resource model.

Grade-control drilling underground using three drill rigs is progressing faster than planned, and sufficient drilling has been completed to reconcile the resource model between the 2080 and 2030 levels in the mine.

The Nova mine is accessed via a decline. Production is processed through a 1,500-mt/d plant that includes conventional crushing, grinding by an open-circuit SAG mill followed by a ball mill in closed circuit, and sulphide flotation to produce separate nickel and copper concentrates.

After ramping up to full production, the project will produce 27,000 mt/y to 30,000 mt/y of nickel, 9,000 mt/y to 10,000 mt/y of copper, and 900 mt/y to 1,000 mt/y of cobalt in concentrates. Concentrates will be trucked both to Nickel West’s processing facilities at Kambalda and to the port of Esperance for export. The haul distances are 294 km to Kambalda and 380 km to Esperance.

The current JORC-compliant mineral resource totals 14.3 million mt, grading 2.3% nickel, 0.9% copper and 0.08% cobalt.

Independence Group acquired the Nova project when it acquired Sirius Resources in 2015 in a transaction valued at about A$1.8 billion.