A recent airborne survey flown by White Cliff Minerals has uncovered multiple big copper targets at its Hulk prospect, part of the company’s Rae copper project in Canada’s northern Nunavut Territory. The discovery has opened up potential for large-scale sediment hosted copper.
The three new conductors appear to reach more than 10km in length and dip to the north into White Cliff’s recently granted leases, sitting in a covered structure within the main Rae Group of sediments. They also line up well with a recent rock chip assay grading 1.65 per cent copper which was picked up during a maiden survey earlier in the month.
To scan the 2,400 line-kilometres across the project area the company employed cutting-edge “MobileMT” technology for the geophysical survey which remarkably, uses natural electromagnetic fields generated by lightning strikes. The fields move between the Earth's surface and the ionosphere, creating electric currents underground, which help detect geoelectrical data more than 1km deep.
The targets, dubbed Targets A, B and C appear as fault-controlled zones and extend along a 20-kilometre strike length with mineralisation down to depths of 300m. The most notable fault is the Herb Dixon structure which is a known conduit for copper-rich hydrothermal fluids.
The Herb Dixon Fault, a key north-south geological feature within the project, plays a critical role by cutting through the Hulk area. Rock chip samples taken along the fault to the south which intersects another White Cliff prospect known as the Vision prospect, have returned exceptional copper grades including 64.02 per cent, 62.02 per cent, 55.01 per cent and 50.48 per cent, emphasising the area's mineral-rich potential.
The easternmost Target A is notable for sitting less than 2km from a 2015 drill hit by Kaizen Discovery Corp that intercepted 29m grading 0.57 per cent copper. The sub-basin spans 36 square kilometres and sits on the eastern boundary of the Herb Dixon fault.
Target B, also adjacent to the Herb Dixon fault, shows strong conductive signatures, while Target C is controlled by two further faults and includes a recent surface assay which threw up the 1.65 per cent copper rock chip.
White Cliff Minerals managing director Troy Whittaker said: “The recently expanded Hulk District now has multiple, independent and coincident datasets that demonstrate sediment hosted copper mineralisation. The identification of three sub-basins along a 20km strike length provides us with significant scope for multiple copper discoveries”.
Whittaker went on to say the alignment of conductive signatures across the sections, combined with the matching chemical and rock chip assays at Hulk, can only be explained by one of a few possibilities, one of which is a substantial metal occurrence.
With the new data and previous field assays from Rae, the company will now fine-tune its studies and zero in on drilling targets for the 2025 program – a campaign which management says is likely to be expanded in light of the positive results.
The Hulk district remains open to the north and White Cliff is now well placed to chase it after its recent land acquisitions that broaden the project footprint in that area. Further analysis of the survey data is underway with additional updates expected before year’s end.
Given the strong indications of mineralisation at Hulk and the overall potential for sediment-hosted copper deposits across the 152 square kilometre exploration area, its perhaps not surprising that the company has chosen to expand its ground holdings directly to the north.
The district is best known for the ‘Coppermine River Group’ flood basalts which are some of the biggest in the world and feature extremely high-grade copper of more than 45 per cent.
However the area has barely been previously explored and apart from the single exploration hole in 2015, the only other historic evidence comes from the records of historic tools and idols made of native copper by the local Inuit in the seventeenth century. A report of a 2 kg copper nugget at surface discovered by a prospector called Samuel Hearne who reached the area in 1771 provides additional evidence of historic copper.
If the drilling campaign next year confirms the preliminary findings, the company could be looking at the potential of a significant copper discovery which could cement the district’s status as a new key mineralised area for Canada and its growing reputation for large-scale copper discoveries.
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By James Pearson
