Gravity helps St George define WA rare earths targets

St George Mining’s latest gravity survey program has unveiled four compelling targets with coincident high gravity and prominent magnetic features at its Destiny project, about 100km south-west of the small Western Australian mining town of Kambalda.

The high gravity signatures indicate the potential for similar carbonatite or mafic intrusions found recently to host highly-valuable minerals such as niobium or high-grade rare earths. The company conducted its survey program over six prominent magnetic features at Destiny that it interpreted as late-stage intrusions, with four providing high-gravity signatures.

Mafic intrusions 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 says two of the four targets feature characteristics similar to renowned WA mineralised carbonatites such as Lynas Rare Earths’ Mt Weld project and WA1 Resources’ Luni niobium discovery.

The company believes its interpretation of the intrusives being prospective for mineralisation is supported by its proximity to the Ida Shear Zone, a relatively late-stage fault that could represent a conduit for intrusions. 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: “This combination of high gravity signatures, magnetic geometry and geological setting at Destiny warrants further investigation to determine the potential for any mineralisation to be associated with these distinctive geophysical features. These targets are relatively easy to explore and we consider they have potential for high-grade discoveries, such as Nb-REE mineralisation or Ni-Cu-PGEs.”

The company says four of the magnetic features range in size from 900m to 2.7km in diameter and result from the aeromagnetics it flew late last year.

St George has conducted two drilling programs at Destiny, with both successfully hitting clay-hosted rare earths up to 5125 parts per million and intervals of 42m thick.

Management says drilling along strike south of the intrusions has confirmed high-grade rare earths associated with the Ida Fault and adds holes across the more than 10km of strike have shown mineralisation to be open in all directions. The company’s plan is to complete grid-spaced gravity surveys at three of its bigger C1 and C3 targets, in addition to the C4 target to better outline the area to be targeted for drilling.

Once further gravity data has been received and assessed, drilling is likely to be scheduled for the second half of this year.

St George has a range of projects on its books and they consist of 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 exciting 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 strings to its bow and with both rare earths and lithium prices appearing to be rebounding from recent lows, it will be keen to further explore its many promising targets as a big discovery might just be its destiny.

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