25m at 0.6% Cu Including 1m at 5.7% Cu Confirms Stark Prospect Potential
White Cliff Minerals has reported significant copper assay results from its maiden diamond drilling campaign at the Stark and Hulk prospects in Nunavut, Canada, reinforcing the potential of a large sediment-hosted copper system. The company plans to advance exploration with a Spring 2026 drilling program following promising geophysical data.
- STK25003 drillhole returns 25m at 0.6% copper including 1m at 5.7% copper
- Mineralisation confirmed below and above key redox boundary at Stark
- Geological and geochemical data validate fertile sediment-hosted copper system
- Airborne electromagnetic survey data currently under interpretation
- Spring 2026 drilling planned to target untested extensions to east and north
Expanding Copper Mineralisation at Stark
White Cliff Minerals Limited (ASX – WCN) has released encouraging assay results from its maiden diamond drilling campaign at the Stark and Hulk prospects within the Rae Copper Project, located in Nunavut, Canada. The standout intercept, drillhole STK25003, returned 25 metres grading 0.6% copper starting at 240 metres downhole, including a high-grade core of 1 metre at 5.7% copper. This mineralisation lies approximately 500 metres south of a previous hole, STK25001, and importantly, occurs below the targeted redox boundary, a key chemical horizon controlling sediment-hosted copper deposits.
The confirmation of mineralisation both above and below this redox boundary is a significant development. It validates the company's geological model that targets this chemical gradient as a trap for copper mineralisation. The redox boundary marks the interface between the Rae Group sediments and the underlying Husky Creek Formation basement rocks, a setting analogous to prolific sediment-hosted copper districts globally.
Geological Context and Exploration Significance
The Rae Copper Project hosts both volcanic-hosted and sediment-hosted copper systems, with the Stark and Hulk prospects representing the latter. Sediment-hosted copper deposits are globally important, supplying around 20% of copper production and often containing cobalt and silver as by-products. The Rae Project's geological framework, supported by recent drilling and geochemical data, indicates a highly fertile copper mineralising system with substantial strike potential exceeding 70 kilometres.
Drillhole STK25001 previously confirmed mineralisation above the redox boundary, returning intervals including 7 metres at 0.4% copper and 3.5 metres at 7.2% copper in the basement rocks. Together with STK25003, these results demonstrate consistent copper mineralisation across wide intervals, reinforcing the prospectivity of the sediment-hosted system. The mineralisation remains open to the east and north, where follow-up drilling is planned.
Advancing Exploration with Geophysics and Drilling
Complementing the drilling results, White Cliff Minerals completed an airborne electromagnetic survey over the prospective horizon. The data is currently being processed and interpreted, with the company confident it has identified mineralisation signatures from both geophysical and geochemical datasets. This integrated approach is guiding the design of the next drilling phase.
Following a successful maiden campaign, the company has secured a high-performing drilling rig on site at its Hope Lake Camp and completed prepayments for the next phase. The Spring 2026 drilling program aims to test untested extensions of the mineralised system to the east and north, maintaining momentum in the exploration effort.
Historic Context and Future Potential
The Rae Copper Project area has a rich exploration history, including a historic resource estimate at the Danvers prospect of approximately 4.16 million tons grading 2.96% copper. While this estimate is not compliant with current JORC standards and requires validation, it underscores the district's potential. White Cliff Minerals’ recent drilling results align with the geological framework observed at Danvers, suggesting a shared mineralisation style and encouraging further exploration.
Managing Director Troy Whittaker highlighted that the results continue to build the geological story at Stark, confirming a significant copper system developing along the unconformity between sedimentary and basement rocks. The company’s integrated exploration strategy combining drilling, geophysics, and geochemistry positions it well to unlock the Rae Project’s potential.
Bottom Line?
With mineralisation open along a vast redox boundary and new geophysical insights, White Cliff Minerals is poised for a pivotal 2026 drilling season.
Questions in the middle?
- How will the upcoming Spring 2026 drilling refine the understanding of mineralisation continuity and grade?
- What insights will the airborne electromagnetic survey provide about deeper or lateral extensions of the copper system?
- How might metallurgical and environmental studies influence the project's development potential?