Edinburgh Park Exploration Faces Uncertainty as No Economic Mineralisation Found Yet

Edinburgh Park – A Province-Scale Gold Exploration Endeavour

Great Southern Mining Ltd (ASX – GSN) has provided a detailed update on its Edinburgh Park Project in northern Queensland, where it holds a joint venture with global miner Gold Fields Ltd. The project spans a vast 1,560 square kilometres in a region renowned for significant gold systems, including Ravenswood and Mt Leyshon. Gold Fields, through a A$15 million option and joint venture agreement, is earning up to a 75% stake by funding exploration activities.

In 2025, Gold Fields completed six diamond drill holes across three key targets – Leichhardt Creek, Megan Veins, and Molongle. While assays from the Leichhardt Creek holes have returned no economic concentrations of minerals, the presence of extensive quartz-sulphide veining and intense hydrothermal alteration signals the potential for intrusion-related gold systems (IRGS) within the northern part of the project.

Initial Drilling Results and Geological Insights

The Leichhardt Creek drilling intersected pervasive phyllic alteration and porphyry-style veining, with one hole revealing a narrow vein containing elevated base metals including silver, copper, zinc, and lead. Although these findings fall short of immediate economic viability, they reinforce the geological prospectivity of the area. Assays for the Megan Veins and Molongle targets remain pending, with results expected in early 2026.

Molongle, identified as a high-priority target, features outcropping epithermal-style hydrothermal breccias with historic surface rock chips grading up to 5.27 g/t gold. The Megan Veins target, characterized by laminated quartz veins and strong argillic alteration, has yielded rock chips up to 10.55 g/t gold, underscoring its exploration appeal.

Mt Dillon – The Next Frontier for Drilling

Looking ahead, drilling is scheduled to recommence after the northern Queensland wet season, likely in March or April 2026. The immediate focus will be the Mt Dillon target, where induced polarisation (IP) surveys have delineated a compelling chargeability anomaly at depths of 200 to 300 metres. This anomaly suggests the presence of sulphide minerals within a preserved intrusive system, potentially indicative of a large-scale epithermal or porphyry gold-copper deposit.

Mt Dillon’s geological setting includes a silicified lithocap and advanced argillic alteration consistent with high-temperature hydrothermal systems. Comparable global deposits beneath lithocaps include significant copper-gold mines in Colombia, Chile, and the Philippines, highlighting the potential scale of the target.

Ongoing Exploration and Strategic Partnerships

Gold Fields has met its minimum expenditure commitment of A$2 million and has invested approximately A$7 million to date, demonstrating strong commitment to advancing the project. Further geophysical and geochemical surveys are underway, including plans for an IP survey over the Rhyolite Hill target, subject to heritage agreements with the Biriah traditional owners.

Great Southern Mining’s Managing Director, Matthew Keane, emphasised the early stage of exploration across this vast project and the encouraging signs of large-scale gold systems. The partnership with Gold Fields brings significant technical expertise and financial backing, positioning Edinburgh Park as a promising exploration frontier in northern Queensland.