Mount Keith Mine
| Company type | Subsidiary |
|---|---|
| Industry | Mining |
| Founded | 1995 |
| Founder | WMC Resources |
| Fate | Planned temporary suspension in 2024 |
| Headquarters | Wiluna , Australia |
Area served | Western Australia |
| Products | Nickel |
| Owner | BHP |
Number of employees | 1600 (planned suspension 2024) |
| Parent | BHP |
Mount Keith Mine is an open-cut nickel mining operation situated in Western Australia, managed by BHP as a component of its Nickel West portfolio. Positioned roughly south of Wiluna, the mine was initially developed by WMC Resources before being acquired by BHP in 2005. Operations commenced in 1995, with closure planned for 2024.
Overview
Located at the northern extremity of the Norseman-Wiluna Greenstone belt, Mount Keith hosts nickel sulphide deposits predominantly in dyke and sill geological structures. These mineralizations are found within ultramafic rock formations that date back around 2.7 billion years. When first projected in 1971, the mine was expected to fulfill about 10% of the world's nickel demand. By 1992, reserves were assessed at approximately 270 million tonnes of sulphide ore with a nickel grade near 0.6%, sufficient to sustain production for roughly twenty years.
History
The nickel deposit was identified by Metals Exploration Limited in 1969. Initially, Australian Consolidated Minerals (ACM) owned a 16% interest, which it expanded to full ownership by 1988. Earlier development was hindered due to depressed nickel prices throughout the 1970s and significant infrastructure expenses. However, shifts in Western Australia's mining sector during the 1980s—such as adopting fly-in fly-out workforce arrangements—lowered operational costs and motivated ACM to revisit the project in 1988.
To advance Mount Keith, ACM partnered with Outokumpu in a joint venture valued at approximately $417 million, aiming for production commencement by May 1992. WMC Resources held a 20% interest in ACM as of 1987 but divested it profitably. In 1991, ACM became a takeover target; although WMC declined a full acquisition, it sought control over Mount Keith specifically. Normandy Mining expressed interest in ACM’s gold assets, prompting WMC and Normandy to submit a joint bid for ACM and divide its holdings—WMC acquiring the nickel operations and Normandy taking over gold assets. This transaction concluded in June 1992, reinstating Outokumpu as a 50% partner in the venture.
By February 1993, WMC confirmed its commitment to proceed with construction at an updated cost estimate of A$450 million. Shortly thereafter, Outokumpu sold its share back to WMC, which then initiated construction activities. Workforce numbers peaked at approximately 1,000 during building phases in 1994; plant commissioning began that November, with initial ore shipments occurring in 1995.
Following BHP’s acquisition of WMC Resources in 2005, Mount Keith’s nickel assets were integrated into the Nickel West brand—the leading nickel producer in Western Australia—which accounted for producing 67,000 tonnes out of the state’s total of 180,000 tonnes during 2004–05. At that time, Mount Keith employed around 950 personnel.
In response to market downturns, BHP scaled back mining operations in 2009, resulting in the dismissal of roughly 300 employees.
Confronted with a global surplus of nickel and declining prices, BHP announced on 11 July 2024 plans to temporarily suspend all Nickel West operations beginning October 2024. The mines will be placed under care and maintenance with an operational review slated for February 2027. Despite the suspension, BHP intends to allocate $450 million annually to preserve these assets for potential future recommencement. This shutdown is projected to affect about 1,600 workers; BHP has pledged to provide options for redeployment or redundancy.
Production
Mount Keith forms part of BHP’s Nickel West network alongside the Leinster Nickel Mine, Kambalda Nickel Concentrator, Kalgoorlie Nickel Smelter, and Kwinana Nickel Refinery.
After initial crushing and processing on-site, the nickel concentrate is transported via road to Leinster for drying before being shipped onward.
BHP publishes production statistics for Nickel West as a whole rather than individual sites. During the fiscal year 2020–21, Nickel West produced approximately 89,000 tonnes of nickel—a rise of 11% over the preceding year—with an average sale price near US$16,250 per tonne. Production decreased to about 77,000 tonnes in the following year (2021–22).