How Deep Can Hillgrove Push Nugent’s High-Grade Copper-Gold Mineralisation?

Extending the Depths of Nugent

Hillgrove Resources Limited (ASX: HGO) has unveiled a series of compelling underground diamond drilling results from its Nugent copper-gold deposit, part of the Kanmantoo Copper Mine in South Australia. The latest assays reveal mineralisation extending to depths of 380 metres below the historic open pit, notably surpassing the boundaries of the 2024 Mineral Resource Estimate by at least 60 metres in some areas.

Among the standout results, hole 25KVUG0532 intersected 5.2 metres grading 0.89% copper and 0.07 grams per tonne gold at 295.8 metres downhole, marking the deepest known mineralised intersection to date. Other significant intercepts include 26 metres at 1.21% copper and 0.27 g/t gold and 17 metres at 1.11% copper and 0.38 g/t gold, underscoring the continuity and high-grade nature of the Nugent system.

Implications for Resource Growth and Development

These drilling results are more than just numbers; they reinforce Hillgrove’s confidence in the substantial resource growth potential at Nugent and the broader Kanmantoo project. The grades reported exceed the global Reserve grade of 0.76%, suggesting that the underground deposit could support a robust mining operation with enhanced economic returns.

Hillgrove is actively fast-tracking the development of Nugent, aiming to increase throughput and copper production. The company targets processing the first ore from Nugent through its mill in the December 2025 quarter, signaling a near-term production milestone. This accelerated timeline reflects the strategic importance of Nugent within Hillgrove’s portfolio and the potential to add significant value.

Ongoing Exploration and Future Outlook

The underground drilling program is progressing steadily, with a target of 60,000 metres planned for stope definition and resource expansion. As of April 2025, over 5,000 metres of diamond drilling had been completed, supported by the deployment of a third drill rig. The drilling strategy focuses on delineating the lode geometry, identifying plunge directions, and refining internal structures, which will inform future mine planning and development.

An updated Mineral Resource Estimate is scheduled for release in the fourth quarter of 2025, following a mid-year data close-off. This update will be critical for investors and analysts to reassess the scale and quality of the Nugent deposit and its contribution to Hillgrove’s production profile.

Technical Rigor and Confidence

Hillgrove’s drilling and sampling protocols adhere to stringent quality assurance and quality control standards, with assays conducted by ALS Adelaide using industry-recognised methods. The company’s Competent Person, Caitlin Rowett, has verified the exploration results, lending credibility to the findings. While one hole was curtailed due to groundwater flow impacting drilling conditions, the overall data quality remains robust.

CEO Bob Fulker highlighted the significance of these results, emphasizing the continuity and depth potential of the Nugent mineralisation system and expressing optimism about the deposit’s future growth and production prospects.