Great Southern Mining has expanded gold mineralisation at its Golden Boulder discovery to 3.5 kilometres, revealing promising shallow high-grade intercepts and setting the stage for deeper drilling in 2026.
- Gold mineralisation extended to approximately 3.5km strike length
- Significant shallow gold intercepts reported from late-2025 RC drilling
- Upcoming deep diamond drilling co-funded by WA Government Exploration Incentive Scheme
- Drilling objectives met – infill, southern extension, and first-pass southern structural targets
- Further RC drilling planned to test depth extensions and higher-grade zones at Golden Boulder and Amy Clarke
Expanding the Golden Boulder Footprint
Great Southern Mining Limited (ASX, GSN) has announced a significant extension of gold mineralisation at its Golden Boulder discovery, part of the Duketon Gold Project in Western Australia. The latest reverse circulation (RC) drilling program, completed in late 2025, has extended the known strike length of gold-bearing zones along the Rosemont Shear Zone to approximately 3.5 kilometres. This marks a substantial increase from previous delineations and underscores the prospect’s growing potential within a prolific gold region.
Golden Boulder is strategically located between Regis Resources’ multi-million-ounce Duketon deposits and Genesis Minerals’ Laverton tenure, placing it in a highly prospective corridor. The recent drilling results have confirmed continuity of mineralisation in the northern areas, extended mineralised zones southwards, and identified new mineralisation in previously untested southern sectors.
Shallow Drilling Yields Encouraging Grades
Most of the drilling to date has been shallow, with holes generally less than 100 metres deep, yet the assays have returned notable gold grades. Highlights include intercepts such as 5 metres at 3.5 grams per tonne (g/t) gold from 39 metres, and 2 metres at 5.0 g/t from 86 metres. These results build on earlier high-grade hits, including a standout 6 metres at 6.7 g/t gold, featuring a 1-metre interval at 34.5 g/t.
The mineralisation is hosted in fractionated dolerite with stacked quartz-carbonate veins and sulphide mineralisation, dipping moderately east and plunging gently south. The structural setting aligns with major regional gold deposits, reinforcing the geological model underpinning exploration efforts.
Next Phase, Deep Diamond Drilling and Infill
Looking ahead, Great Southern Mining plans to commence a deep diamond drilling program in February-March 2026. This phase, co-funded by the Western Australian Government’s Exploration Incentive Scheme, aims to test deeper structural controls on mineralisation and provide critical geological data to refine targeting. Following this, further RC drilling will focus on infill and depth extensions at both Golden Boulder and the nearby Amy Clarke prospect.
Managing Director Matthew Keane expressed optimism about the results and the year ahead, highlighting the achievement of all key drilling objectives and the potential for a maiden JORC Mineral Resource estimate. He noted that 2026 could be pivotal for the Duketon Gold Project as the company builds on its recent successes and explores new targets across its extensive tenement holdings.
Strategic Implications for GSN
The extension of mineralisation to 3.5 kilometres along a major shear zone significantly enhances the scale and prospectivity of Golden Boulder. The shallow nature of the mineralisation to date suggests a potentially accessible resource, although true widths and economic viability remain to be confirmed through deeper drilling and resource modelling.
With the upcoming diamond drilling program providing structural insights and testing depth extensions, investors will be watching closely for further assay results and resource updates. The co-funding arrangement with the government also mitigates some exploration risk, allowing GSN to accelerate its evaluation of this promising gold system.
Bottom Line?
Golden Boulder’s expanded strike and shallow high-grade hits position GSN for a transformative 2026 exploration campaign.
Questions in the middle?
- Will the upcoming diamond drilling confirm deeper high-grade mineralisation?
- How soon can GSN deliver a maiden JORC Mineral Resource estimate for Golden Boulder?
- What impact will these results have on GSN’s valuation and potential development timeline?