Great Southern Mining has kicked off a major 15,000m reverse circulation (RC) drilling campaign at its Golden Boulder discovery.
Leading the charge across Great Southern's 100 per cent-owned Duketon gold project, Golden Boulder is rapidly emerging as the flagship prospect as the company works to unlock the full extent of a 3.5km gold corridor.
Golden Boulder lies just 15km southwest of Regis Resources' Garden Well processing plant on the Rosemont-Ben Hur structural corridor, creating future production optionality if a commercial resource is ultimately defined. The corridor is one of several major gold-bearing trends controlled by Great Southern across the Duketon Greenstone Belt.
Unlike a greenfields punt, this is brownfields exploration in a proven gold district where the geological model has already delivered several gold mines and continues to reward explorers.
More than 50 historical workings litter the region, showing where early miners chased rich shallow quartz veins, yet barely scratched what could be a much bigger gold system lurking below.
The new drill program will now chase beneath those old workings after drilling earlier this year confirmed gold mineralisation along three parallel trends – the Main Line, Eastern Line and Ogilvies – with the Main Line now defined over a 3.5km strike and still open at depth, along strike and across potential parallel lodes.
Multiple mineralised trends increase the opportunity to build a larger gold inventory across a broader area rather than relying on a single narrow vein.
Previous drilling in 2025 delivered a string of high-grade hits, including 5m at 14.6 grams per tonne (g/t) gold with a spectacular 1-metre section grading 70.9g/t. Another hole returned 6m at 6.7g/t gold, including 1m at bonanza grade of 34.5g/t.
Great Southern Mining managing director Matthew Keane said: "The recent diamond drilling at Golden Boulder has greatly improved our understanding of the structural and geological settings that host gold mineralisation. More importantly, it has led to a reinterpretation of the orientation of gold-bearing structures, which bodes well for significant depth extensions."
Armed with a new geological model and a $4.6 million war chest from a recently completed equity placement, Great Southern is fully funded for its drilling program.
The work will first tighten drilling across the northern and southern sections of the Main Line to prove the continuity of the gold mineralisation before extending it at depth. The program will also test whether the parallel Eastern Line extends farther south and beneath previous drilling, while hunting for higher-grade zones within the broader system.
The entire campaign is expected to take up to 12 weeks, after which the rig will move 4km northwest to the nearby Amy Clarke prospect, an emerging discovery within the Duketon gold project. Previous drilling there has already outlined 4.7km of mineralisation that remains open along strike and at depth, with past hits including 8m at 6.7g/t gold and 2m at an impressive 23.9g/t gold.
Beyond the Duketon drilling campaign, Great Southern has assembled a healthy pipeline of news flow across its Western Australian gold portfolio.
At the company’s separate Mon Ami gold project, 12km south of Laverton, the RC rig has already completed a 16-hole, 3100m program, with assays expected in the next three to four weeks.
Mon Ami already hosts a 55,500-ounce gold resource on a granted mining lease and, with nearby processing infrastructure, could provide valuable satellite mill feed as exploration continues.
With drilling underway at Golden Boulder, Mon Ami assays only weeks away and Amy Clarke next in line for the truth detector, Great Southern has assembled a compelling pipeline of catalysts around a district-scale gold opportunity underpinned by proven geology, nearby processing infrastructure and several advanced prospects.
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By Penny Taylor
