Geological Breakthrough at Mulga Tank: High-Grade Nickel Sulphides Found Near Surface, Promising Lower Mining Costs
September 21, 2026
Mulga Tank’s geological model is being refined to focus exploration on shallower, higher-grade zones and to better target high-grade massive nickel sulphides within the large ultramafic complex.
Diamond tail results show a substantial sulphide presence near the basal zone, with 442 meters of cumulative nickel sulphide mineralisation averaging 0.26% Ni, 129 ppm Co, 78 ppm Cu, and 27 ppb Pt+Pd.
Within the basal zone at depth, higher-grade mineralisation includes a 74-meter interval at 0.32% Ni, 142 ppm Co, 115 ppm Cu, and 31 ppb Pt+Pd from 762 meters, including a sub-interval of 23 meters at 0.42% Ni, 144 ppm Co, 74 ppm Cu, and 44 ppb Pt+Pd from 812 meters.
The southwest portion of the main intrusion is interpreted as the most uplifted, bringing enriched basal horizons closer to surface and potentially lowering future drilling and mining costs.
Western Mines Group reports a geological breakthrough at Mulga Tank, with diamond drilling extending and deepening a prior RC hole and supporting results from five additional RC holes.
Overall, the results enhance targeting of Western Mines’ high-grade core, support a clearer mine-plan timeline, and align with strong long-term demand for nickel sulphide battery metals amid the energy transition.
Mulga Tank sits in the Minigwal Greenstone Belt as a large mafic-ultramafic intrusion about 190 km northeast of Kalgoorlie, WA, with a mineral resource estimate of 1.97 billion tonnes at 0.27% Ni (over 5.3 million tonnes of Ni), including 565 Mt indicated at 0.28% Ni.
The basal contact—where Ni-Cu-PGE sulphides accumulate as the intrusion cools—is viewed as the key to unlocking the deposit, with uplifted near-surface basal horizons potentially improving drilling efficiency and reducing costs.
Five RC holes intersected broad nickel sulphide zones (ranging 171 m to 98 m intercepts) with Ni grades roughly between 0.21% and 0.30%, validating uplifted basal horizons near the surface.
Summary based on 1 source
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The West Australian • Sep 21, 2026
WMG homes in on Mulga Tank nickel sweet spot in WA