Western Mines hits sulphides in WA nickel-copper hunt

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Matt BirneySponsored
Workers collect samples at Western Mines Group’s Mulga Tank project in WA’s Eastern Goldfields.
Camera IconWorkers collect samples at Western Mines Group’s Mulga Tank project in WA’s Eastern Goldfields. Credit: File

Perth-based mineral explorer Western Mines Group has landed more nickel, copper and platinum-group elements, or “PGE” hits at its flagship Mulga Tank project in Western Australia’s Eastern Goldfields region after plunging another three holes at the site.

The work forms part of an initial 10-hole, 4050m campaign where the company will look to test a flurry of drill-ready targets identified through earlier exploration.

One of the new holes delivered the most frequent occurrence of visible sulphide observed at the project so far, with the bore intersecting seven nickel-copper sulphide veins within an 8m section from 276m.

Western Mines says the veins mainly comprise pentlandite, chalcopyrite and sphalerite, with subsequent portable XRF analysis confirming the presence of sulphides.

The probe was designed to follow up on a historic hole at the site that delivered a 0.25m intercept going 3.8 per cent nickel, 0.7 per cent copper and 0.7 grams per tonne PGE.

Intriguingly, Western Mines says the frequency of veining in the recent hole compared with that of the earlier bore indicates the former may be closer to the source of the ground’s sulphide mineralisation.

The company has since cased the hole ahead of a planned downhole electromagnetic survey that will be used to vector in on off-hole follow-up targets.

In order to evaluate the geology at the neck of a panhandle, a feature extending north-west from the main Mulga Tank body, another hole was drilled to a depth of just over 429m.

After passing through about 108m of sand and conglomerate cover, the hole encountered 268.6m of largely ultramafic rocks before hitting a footwall at a depth of about 376m.

Western Mines says despite the absence of visible nickel sulphide mineralisation down the hole, portable XRF data revealed an encouragingly high magnesium oxide concentration and nickel-to-chromium ratio that could point to bigger things. The hole was cased and will be evaluated later with a downhole electromagnetic survey.

The final hole of the program was sunk to 270m and was drilled to test a shallow electromagnetic target some distance away from the panhandle feature and the main Mulga Tank body. It intersected 150m of Archaen basalt beneath 96m of sand cover, sitting on a footwall of shales and sediments rich in pyrite, pyrrhotite and minor chalcopyrite.

According to Western Mines, the sulphides in the sedimentary footwall unit are linked to parallel stringer veinlets that could explain the electromagnetic anomaly.

The company says it has now sent samples from each hole for geochemical assay analysis.

Following the three-hole sulphide hunt at Mulga Tank, Western Mines has mobilised the rig south and begun drilling a single planned hole.

The exploration is set to target the western margin of the project’s key dunite intrusion and test a zone beneath another historic hole that delivered a 1m intercept going 1 per cent nickel and 0.5 g/t PGE.

Western Mines considers the intrusion highly prospective for nickel-copper-PGE mineralisation.

Is your ASX-listed company doing something interesting? Contact: matt.birney@wanews.com.au

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