St George Mining has jumped into a new critical minerals exploration program for lithium, rare earths and copper at its district-scale Woolgangie project within the fertile Coolgardie Mineral Field in Western Australia.
The site sits adjacent to operating lithium mines and where historical drilling previously identified rare earths and copper anomalism. It will be the company’s first drilling program at Woolgangie, which it acquired in February.
St George says the 3350-square-kilometre project, comprising seven granted tenements and 15 in application, is being subjected to advanced modern exploration techniques in a bid to elucidate economic mineralisation where tantalising indications have been revealed from historical activity. The project has been divided into three strategic areas – the Central, Eastern and Western tenements.
The Central tenement’s exploration focus is along the 90km strike length of the Ida Fault, which controls significant lithium deposits such as Liontown Resources’ Kathleen Valley that has a mineral resource estimate of 156 million tonnes at 1.4 per cent lithium oxide and 130 parts per million tantalum oxide, and Delta Lithium’s Mt Ida play with 12.7 million tonnes at 1.2 per cent lithium oxide.
Management says near-surface extensive rare earths anomalism suggesting an ionic clay-hosted model is indicated in historical intercepts from drilling by Mincor Resources in 2010 while it was exploring for nickel sulphides in two areas, some 30km apart. From the southern area, two reverse-circulation (RC) drillholes returned assays of up to 36m at 556ppm million cerium-lanthanum-yttrium from 20m.
Moreover, 16 of 36 rotary air-blast (RAB) drillholes in the same area yielded up to 27m of 257ppm lanthanum from 3m, where it was the only minerals reported in assays. The northern area gave a best assay result of 20m at 567ppm cerium-lanthanum-yttrium from 86m from four drillholes. Notably, the samples from historical drilling were not assayed for heavier rare earths and provide what St George believes could be further upside economic potential.
And if that was not enough to whet an explorer’s appetite, historical drilling by Mincor on Emu NL’s tenements in 2010 – in work that was focused on electromagnetically-identified conductors – revealed highly-significant anomalous copper sulphides in several drillholes and returned assays up to 50m at 0.2 per cent copper and 2.1 grams per tonne silver. The company says mineralisation is open at depth, with a host rock yet to be determined.
A new ground-based moving loop electromagnetic (MLEM) survey will be conducted over the historically EM-identified conductors to optimise modelling and investigate at greater depths to the previous survey. It is expected to refine the model for future drilling.
Most of the exploration focus will be on the prospective northern portion of the Central tenement, where management says historic rare earths anomalies occur. A maiden drill program of some 60 air-core (AC) holes for about 2500m has begun in an area of 55sq km and is due to be completed next week, with assay results to be returned in four to six weeks and follow-up metallurgical testing to be conducted as required.
A high-resolution airborne magnetic (AMAG) of 9000 line kilometres, with a 100m line spacing, will also be run over a large portion of the northern area to help better define the structural geology and guide future drill targets.
The Eastern tenements are highly prospective, with close proximity to several operating lithium operations such as Mineral Resources’ Mt Marion mine with 71.3 million tonnes at 1.37 per cent lithium oxide and Tawana Resources’ Bald Hill mine holding 26 million tonnes at 1 per cent lithium oxide.
The first of several planned soil surveys has begun, with further intentions for additional rock-chip sampling and field mapping of lithium-bearing pegmatites within the tenements. The company says its Western tenements are also prospective for rare earths, given historical intercepts and geological setting.
St George Mining executive chairman John Prineas said: “. Woolgangie offers an excellent opportunity for a new discovery in an area of the Eastern Goldfields that has seen very limited exploration other than for gold and nickel. Woolgangie is an example of how St George is building out our portfolio of highly prospective exploration assets to deliver a pipeline of value-creating opportunities for shareholders. St George will be an active explorer for the remainder of this year.”
Mr Prineas said the company was also planning the next phase of lithium exploration at its Mt Alexander project and maiden field programs for the lithium-prospective tenements acquired recently through the company’s subsidiary, Lithium Star.
Critical metal followers could do well to keep an eye out for St George as it pursues its green pastures with a modern exploration program in a mineral province hotspot.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By Gary Kjellgren
