Western Mines strike sulphides at Mulga Tank in WA

Western Mines says the final assays from drilling at its flagship Mulga Creek Tank project in WA have confirmed disseminated sulphide mineralisation which appear similar in style to the mineralisation found at BHP’s Mt Keith Mine. The phase 1 drilling campaign at the company’s nickel-copper-platinum group elements, or “PGE” project, will be followed up with extended work to better understand the architecture of the system and pinpoint vectors to high-grade mineralisation.

Mulga Tank, about 190 kilometres east of Kalgoorlie, takes in about 400 square kilometres of scantly explored terrain in the Minigwal Greenstone Belt. Western Mines says only 12 historical holes have gone deeper than 200m and nearly all show nickel-copper-PGE sulphides.

The company completed its 10-hole diamond drilling program totalling 3,990 metres at Mulga Tank between April and July this year. The campaign was designed to test a wide range of geological and geophysical drill targets from previous exploration targeting work.

Results from the first five holes were reported in August and September however, the remaining assay results were delayed.

MTD020, the ninth hole of the campaign and drilled to about 564m, was of particular interest to Western Mines and was designed to test beneath historical hole MTD011 which produced numerous intersections of nickel-copper-PGE mineralisation.

Western Mines reports these final batches contain a near-complete profile down the entire length of hole MTD020. Sampling from other holes was limited to intervals where nickel sulphide blebs and veinlets were observed or samples taken from the basal contact of each hole.

The company previously reported MTD020 intersected a 450m thick package of high magnesium oxide dunite ultramafic containing disseminated magmatic sulphides. Two styles of visible nickel mineralisation were observed down the hole including remobilised nickel sulphide veins, or pentlandite-pyrrhotite and disseminated magmatic sulphides, or pyrite-pyrrhotite-pentlandite.

Western Mines says the latest geochemical assay results now confirm the potential for an extensive working mineral system which appears to be similar to the disseminated sulphide system found at BHP’s operating Mt Keith Mine.

Best individual element results of MTD020 were up to 0.68 per cent nickel, 0.036 per cent copper, 0.027 per cent cobalt and 224 parts per billion platinum and palladium. It also reported a continuous intersection of 175m at 0.27 per cent nickel, 0.01 per cent copper, 0.015 per cent cobalt and 21ppb platinum and palladium that also averaged 0.49 per cent sulphur.

The 2022 diamond drilling program, including MTD020, has demonstrated clear lithogeochemical and textural indications that Mulga Tank is a live system in terms of magmatic nickel-PGE sulphide potential, with large volumes of the complex still completely untested.

Work will continue now to better understand the broader architecture of the system and pinpoint vectors to high-grade mineralisation.

The project contains the entire Mulga Tank Dunite Intrusive – a major ultramafic intrusion approximately the same size as the nearby Kambalda Dome camp with its 35 million tonne resource returning 3.1 per cent nickel.

Mt Keith is WA’s second largest contained nickel deposit.

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