OZ Minerals lifts West Musgrave ambitions

The company plans to increase its annual production at West Musgrave by 15 per cent to around 32,000 tonnes a year of copper, while lifting its nickel output by 20 per cent to around 26,000 tonnes a year

Alongside the upgrade, OZ Minerals will lift its processing plant throughput from 10 million tonnes a year to 12 million tonnes.

This owes to additional grinding circuit capacity, while allowing the company to keep its capital costs to a minimum.

“During the PFS, we took an innovative approach to the mineral processing plant with the adoption of vertical roller mills as opposed to the traditional SAG and ball mill circuit,” OZ Minerals managing director Andrew Cole said.

“By partnering with a market leader of vertical roller mills during the study update, we have been able to leverage additional grinding circuit capacity on the back of further pilot plant test work and increase throughput with minimal increase to capital costs.”

The plant throughput increase will reduce the processing operating costs and allow OZ Minerals to increase in the size of the open pits and both the mineral resource and ore reserve.

The ore reserve at West Musgrave now stands at 253 million tonnes at 0.35 per cent copper and 0.32 per cent nickel.

This represents around 22 years of the project’s 26-year life of mine.

The West Musgrave project is now valued at around $1 billion, accounting for around $4.5 billion in cashflow over the life of mine.

OZ Minerals will now continue its study of the project via a $67 million investment and aims to make a final investment decision in 2022.