White Cliff Minerals Expands Hulk Copper System Over 3.7 Kilometres

Visible Copper Sulphides Confirm Large-Scale System

White Cliff Minerals Limited (ASX:WCN) has revealed further diamond drilling results that reinforce the Hulk sediment-hosted copper system at its Rae Copper Project in Nunavut, Canada, as a major discovery. The 2026 drilling campaign intersected visible chalcopyrite copper sulphides consistently along the Rae Group-Husky Creek Formation redox boundary, a geological contact identified as the primary control on mineralisation. This latest phase has expanded the known mineralised footprint by 3.7 kilometres east of the 2025 discovery hole STK25004, stretching the system to approximately 6.3 square kilometres.

Geological Model Validated by Regional Step-Out Drilling

The drilling program deliberately employed widely spaced regional step-outs to test the lateral extent of the copper horizon, which is developed as a sheet-like, stratiform zone typically 2 to 30 metres thick. Holes SED26001 and SED26002 both intercepted visible chalcopyrite mineralisation within basal Rae Group conglomerates directly at the unconformity with the underlying Husky Creek Formation. These observations confirm continuity of copper sulphides across the Rae Group sub-basin at Hulk, supporting the company's geological model that positions the redox boundary as a key depositional control.

Chalcopyrite occurs mainly as cement and veinlets concentrated along the unconformity, consistent with sediment-hosted copper deposit styles globally. The system’s scale and style bear resemblance to major sediment-hosted copper provinces, which typically feature thin but laterally extensive mineralised horizons.

Targeting Higher-Grade Bornite Zones and New EM Anomalies

Building on the 2025 drilling that included notable intercepts such as 3.5 metres at 7.2% copper and 25 metres at 0.6% copper, White Cliff is now vectoring towards the core of the mineralised system. The 2026 program aims to focus on zones exhibiting stronger alteration and higher-grade bornite-rich mineralisation, which could enhance the project's economic potential.

Additionally, the company plans to test further high-priority targets where electromagnetic (EM) surveys have identified conductivity anomalies at depths comparable to previous discoveries. These unexplored anomalies offer significant potential for expanding the Rae Copper Project’s resource base.

Historical Context and Rigorous Exploration Standards

The Rae Copper Project covers 1,228 square kilometres in Nunavut and includes multiple targets such as Hulk and Danvers. The region has a rich exploration history dating back to the 1960s, with historic resource estimates at Danvers indicating 4.16 million tons at 2.96% copper, though these are not JORC-compliant and require modern validation.

White Cliff’s current drilling and sampling protocols follow rigorous industry standards, including comprehensive quality control measures and laboratory assays conducted by ALS Yellowknife. Visual observations of mineralisation are preliminary, pending assay results expected within four weeks. The company’s geological and exploration teams are systematically building a robust dataset to underpin future resource estimation and development studies.

Managing Director Highlights District-Scale Potential

Managing Director Troy Whittaker emphasised the significance of the findings: "Hulk continues to deliver on exactly what we set out to test, a large, laterally extensive copper system developed along the key Rae Group-Husky Creek Formation contact. Every drillhole completed at Hulk this year has intersected visible chalcopyrite at this key contact, reinforcing the redox boundary as the primary control on mineralisation."

Whittaker added that these results validate the company’s geological model and targeting approach, reinforcing the view that Hulk could evolve into a major basin-scale copper system.