History of Kambalda’s fist nickel mine


Silver Lake nickel mine was developed on the Lunnon Shoot, named after diamond driller Jack Lunnon who drilled the discovery hole, KD1, in 1966. The mine was operated by WMC continuously from 1966 until its closure in the 1985/86 financial year, producing 4.54 million tonnes of ore at 2.72% Ni for over 123,000 tonnes of nickel metal based on WMC’s production records. The Silver Lake mine and the nickel shoots it hosts are developed on the southeast flank of the Kambalda Dome, with the historical workings plunging for approximately 2.5km to the south-southeast and extending over a vertical distance of at least 350m (from lake surface to 50m below sea level).

History of Kambalda’s First Nickel Mine

Silver Lake nickel mine was developed on the Lunnon Shoot, named after diamond driller Jack Lunnon who drilled the discovery hole, KD1, in 1966. The mine was operated by WMC continuously from 1966 until its closure in the 1985/86 financial year, producing 4.54 million tonnes of ore at 2.72% Ni for over 123,000 tonnes of nickel metal based on WMC’s production records. The Silver Lake mine and the nickel shoots it hosts are developed on the southeast flank of the Kambalda Dome, with the historical workings plunging for approximately 2.5km to the south-southeast and extending over a vertical distance of at least 350m (from lake surface to 50m below sea level).

Isometric view (looking down to the northwest) of the Silver Lake-Fisher project area highlighting interpreted nickel trends (sourced from 1990 WMC technical report) and the prospective SLHW Exploration Target.

First-time Mineral Resource for Silver Lake

Lunnon Metals announced a first-time Mineral Resource for the 25H deposit at Silver Lake on 4 December 2023. The 25H is located at the south end of the Silver Lake mine, at the Kambalda Gold & Nickel Project (KGNP). This first-time MRE follows receipt of final assays from the Company’s first pass surface diamond drill (DD) program into the deposit. The 25H MRE stands at 824,000 tonnes at 1.7% nickel for 13,800 contained nickel tonnes, comprising:

  • 336,000 tonnes @ 1.6% Ni for 5,300 nickel tonnes in Indicated Resource; and
  • 488,000 tonnes @ 1.7% Ni for 8,500 nickel tonnes in Inferred Resource.

Key implications of this initial 25H MRE include:

  • Demonstration of potentially economic mineralisation on the Silver Lake – Fisher (SLF) project for the first time, since the deal to acquire the nickel rights from Gold Fields Ltd on these tenements settled in October 2022.
  • Development of an initial Mineral Resource base immediately adjacent to the Company’s high-priority Long South Gap exploration area, the site of the recently completed, extensive 3D seismic survey by UltraMag Pty Ltd.
  • Potential remains for high-grade shoots to be contained within the broad 30m to 170m current surface DD hole spacing
Plan view of the 25H prospect area showing historical pierce points and the recent LM8 drill program together with the position of the historical mine workings (black) and current surface infrastructure (see long projection below for fuller results).

Mineral Resource long projection looking WSW, illustrating areas of Indicated (red), Inferred (green) and unclassified (blue) categorisation.

Silver Lake – Long South “Gap”

To the north and east of the Silver Lake Hanging Wall Exploration Target area, the Company is working with external consultants to plan a 3D seismic survey to provide detailed geophysical data input into the targeting of the area directly south of Mincor Resources NL’s McLeay and Moran deposits (previoulys owned by ASX:IGO), hosted at the south end of their Long Operation. This target area will be referred to in future reporting to the market as the “Silver Lake-Long South Gap”. Once the survey is planned the Company will provide an update on the timing of its execution and next steps.

Plan: source ASX:IGO. Amended with Lunnon Rights Area boundary (yellow) on IGO’s 2011 Diggers presentation (IGO nickel metal tonnes figures not current)