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Lake Johnston Lithium Project

Lake Johnston Lithium Project

The Lake Johnston Lithium Project is located 450km east of Perth, Western Australia, in the central part of Yilgarn Lithium Province, which hosts the majority of Australia’s Lithium Mineral Resources.  Charger currently owns 100% of Project after purchasing Lithium Australia’s minority Interest.  (See ASX Announcement dated 20 Nov 2023 – Rio Tinto and Charger Metals sign Farm-in Agreement for the Lake Johnston Lithium Project)

Binding Farm-in Agreement with Rio Tinto

Rio Tinto Exploration (“RTX”), a wholly-owned subsidiary of Rio Tinto Limited (ASX: RIO), to Farm-in to the Lake Johnston Project:

  • RTX paid Charger $500k and invested $1.2 million in Charger prior to commencement of farm-in
  • RTX to spend minimum $3 million exploration expenditure over the first 12 months
  • RTX can earn 51% by sole funding $10 million in exploration expenditure and paying Charger minimum further cash payments of $1.5 million
  • RTX can earn 75% by sole funding $40 million in exploration expenditure or completing a Definitive Feasibility Study

Location map of Lake Johnston Lithium Project in relation to other Yilgarn Block lithium projects.

This location is not only highly prospective for lithium mineralisation but benefits from excellent infrastructure. This includes easy access to the road and rail corridor​ between Kalgoorlie and Esperance, which both in turn lead to the port infrastructure at Esperance and Fremantle.

Approximately 70km to the West of Lake Johnson is the Earl Grey (Mt Holland) Lithium Project, one of the largest undeveloped hard-rock lithium projects in Australia, with the Earl Grey Deposit resource1 estimated at 189 Mt at 1.5% Li2O. This is under development by Covalent Lithium Pty Ltd, which is the manager of a JV between subsidiaries of Sociedad Química y Minera de Chile S.A. (“SQM”) and Wesfarmers Limited.

The lithium prospects at Lake Johnston occur within a 50km long corridor along the southern and western margin of the Lake Johnston granite batholith.

Initial geochemistry and geophysics confirmed several highly prospective target areas at Lake Johnson, with potential for scale and grade, including the Medcalf and Mt Day prospects

Lake Johnston Lithium Project Location approximately 450km east of Perth and 70km east of the Earl Grey Lithium Project (Covalent Lithium Pty Ltd).

Medcalf Prospect

Rock chip samples of outcropping pegmatites at Medcalf confirmed high-grade lithium in spodumene, with results between 1.51 – 7.15% Li2O.

A maiden 41-hole RC drilling programme subsequently completed at Medcalf delineated a swarm of stacked spodumene-bearing pegmatites within a 100m wide corridor, over 250m down dip, and over a 700m strike. Multiple high-grade zones were intersected, such as 5m @2.55%Li20 from 68m (22CRC002).

Left: Drill collars relative to the surface mapped pegmatite swarm at Medcalfe
Right: Cross section A-A’ at Medcalfe showing an interpretation of the pegmatite swarm

With this maiden drilling having confirmed high-grade lithium in spodumene pegmatites, Charger believes the potential for scale remains open, and preparations are underway for follow up extensional drill programmes both down dip and along strike.

Mt Day Lithium Prospect

The Mt Day Prospect is located ~25km northwest of the Medcalf Prospect, close to the Hyden-Norseman highway. It is a large lithium-caesium-tantalum (“LCT”) pegmatite field defined by strong lithium soil anomalies extending for 5.5km x 1.5km, which are coincident with mapped pegmatites. Rock chip samples of the outcropping pegmatites demonstrate high-grade lithium and tantalum mineralisation, and the Company is working towards its maiden drill programme at Mt Day to test for lithium mineralisation at depth.

Left: Mt Day Prospect, showing named and mapped pegmatites, with Li2O and Ta analyses from rock chips, overlaying an image of lithium index value
Right: (same map as above): Lake Johnston Lithium Project Location approximately 450km east of Perth and 70km east of the Earl Grey Lithium Project (Covalent Lithium Pty Ltd).