Lake Johnston Project
The Lake Johnston Project is a new tenure covering +50 km strike of Lake Johnston Greenstone Belt, which consolidates the southern region for the first time.
- Total tenement area of 337km2
- Favourable komatiite host for nickel sulphide extends for the entire length of Project
- Contemporary geological model for intrusive nickel sulphide formation not previously considered
- New generation geophysics better suited to penetrate deep weathering and identify mineralisation under conductive cover
- Extensive historical work provides a good foundation for exploration
Located between two prolific WA greenstone belts, the Lake Johnston Greenstone Belt is geologically similar to the prolific gold and nickel producing Norseman-Wiluna and Southern Cross greenstone belts. Historically overlooked and under-explored – Lake Johnston was never the main project focus for the “nickel majors” that held the ground historically. TG Metals has the most significant land package ever held by one company in the history of exploration within the Lake Johnston Greenstone Belt.
Historical Komatiitic Nickel Focus
The project has significant untested potential for nickel sulphide mineralisation. Nickel sulphide hosting ultramafic rocks are mapped south from the Emily Ann – Maggie Hays mining centre – through the whole Lake Johnston Project. Basement/fresh rocks are not well tested for sulphide mineralisation. Multiple indicators of sulphide mineralisation require followed up Numerous geophysical conductors identified remain untested or poorly tested – potential indicators of massive sulphide mineralisation. Modern higher-powered techniques, better suited to test for sulphides below weathering profile, to be employed at priority target areas. Project well leveraged off past exploration data and refined techniques.
Defined Ni Co Laterine Deposits
The majority of the historical drilling is shallow – testing only the oxide material. Multiple drill results of +1% nickel and cobalt up to 6,900 ppm defines large nickel-cobalt oxide (surficial/lateritic) deposits. Any “Exploration Target” for nickel-cobalt oxide deposits stated by past operators is not compliant with the JORC Code – TG Metals is currently updating target numbers. Presents a compelling early resource definition activity post IPO. Less than 140km to Ravensthorpe Nickel Operations.
The Lake Johnston Greenstone Belt hosts defined Lithium-caesium-tantalum (LCT) pegmatites – a source of about one-fourth of the world’s lithium production and most of the tantalum production. TG Metals has discovered the Burmeister Lithium Prospect, a series of stacked shallow dipping spodumene bearing pegmatites. The pegmatites are “blind” under cover with no outcrop and were discovered by drilling beneath prominent lithium soil anomalies. TG Metals continues to drill define the highly mineralised pegmatites with widths up to 19m drilled so far and grading 1.52% Li2O over the full width of the pegmatite.
The soil anomalies are large and drilling has defined spodumene bearing pegmatites up to 1400m along strike of the Burmeister soil anomaly. The company continues to drill test these high grade pegmatites, establishing the geological model which will guide future resource drilling. The large Jaegermeister soil anomaly to the east of the Burmeister discovery, will be progressed with drilling in 2024 once all approvals have been gained.
Despite a long history of exploration in the Lake Johnston Belt, surficial cover and deep weathering have made discovery a challenge. TG Metals is overcoming these challenges through modern Geophysical and Geochemical techniques. Already the new Geochemistry via lithium soil sampling has been successful in discovering blind lithium pegmatites at the Burmeister discovery. In addition, TG Metals has employed high powered ground electromagnetic (EM) geophysical tools to define nickel sulphide drill targets. LIDAR has also been effective in defining topographical features which show previously unseen subsurface structures. TG Metals has a staged approach to mineral exploration which focusses in on mineral occurrences and deploys drilling in a targeted cost-effective manner.
The Company intends to continue it’s staged, targeted approach, employing modern techniques to capitalise on mineral targets which have not been being fully tested or completely missed in past exploration.