St George to use gravity to drag it closer to WA rare earths

St George Mining is planning to launch a grid-spaced gravity survey next month at its intriguing C1 rare earths prospect at the company’s Destiny project, about 100km south-west of the Western Australian mining town of Kambalda.

The company will conduct a grid-spaced 200m-by-200m gravity survey that has been designed to home in on discrete targets within the C1 core, which features a 2.1km-diameter magnetic and gravity-high.

St George believes the exploration potential of C1 has increased due to the sizeable magnetic feature coupled with a recent gravity survey that highlights a gravity-high signature in the core. It says the signature is consistent with a dense body and increases the possibility for the type of mafic or carbonatite intrusion that has been found recently to host highly-valuable minerals such as niobium or high-grade rare earths.

Management says the combination of magnetic and gravity highs supports the potential for one of those intrusions. The adjoining Mt Ida Shear Zone is  a relatively late-stage structural fault that could represent a conduit for intrusions of mantle-derived magma, leading to the presence of mineralisation.

Also providing support to its belief is evidence of major structural disruptions to the greenstone-granite belts that surround the interpreted intrusions.      

St George Mining executive chairman John Prineas said: “We are prioritising exploration at C1 in light of its similarities to known mineralised carbonatites in Western Australia – such as Mt Weld and Luni. The large scale of C1 supports the potential for a significant greenfields discovery and we look forward to drilling this exciting target soon.”

The C1 prospect is one of six magnetic features the company tested with the gravity survey in April, with four of them interpreted to be late-stage intrusions and therefore possible carbonatite or mafic intrusive-bodies.

Management says C1 has geological characteristics similar to carbonatites at Lynas Rare Earths’ Mt Weld project and WA1 Resources’ ground. WA1’s “coffee-spitting” niobium discovery sent its shares into orbit, increasing from 14c in October 2022 and hitting a high of $23.20 on May 20 this year.

The difference with mafic intrusions is they are known for hosting nickel, copper and platinum group elements (PGE) in economic quantities, with IGO’s Nova-Bollinger mine and its stunning nickel-copper-cobalt discovery made back in 2012 a prime example.

St George plans to drill in the second half of this year and has initiated program of works (POW) and heritage clearance surveys in anticipation of the drilling. It has already conducted two drilling programs at Destiny, with both successfully hitting clay-hosted rare earths up to 5125 parts per million and intervals up to 42m thick.

Management says drilling along strike south of the intrusions has confirmed high-grade rare earths associated with the Mt Ida Fault and adds that holes across the more than 10km of strike have shown mineralisation to be open in all directions.

St George has a range of projects on its books comprising 3337 square kilometres of granted exploration licences, with a further 5533sq km of tenements under application.

Alongside its prospective rare earths arm, the company has seven hard rock lithium projects that are bundled under its subsidiary company, Lithium Star. It holds a 90 per cent interest in the venture, with the world’s leading lithium-ion battery maker TDK Corporation’s subsidiary, Amperex Technology, recently purchasing a 10 per cent stake in the lithium hopeful.

St George has many projects with the potential to find “in-demand” valuable minerals and its next gravity and drilling program at Destiny might bring it one step closer to success.

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