Great Southern Mining looks to be turning its Golden Boulder prospect from a promising gold prospect into something far more substantial, with new assays confirming high-grade mineralisation from surface and continuity across the first 1.1km of a 3.5km mineralised trend in Western Australia’s Duketon Belt.
The results come from the company’s ongoing 14,000-metre reverse-circulation (RC) drilling program at Golden Boulder, a discovery within its 100 per cent-owned Duketon gold project. The 549-square-kilometre holding sits in the Laverton–Duketon district and captures some serious gold-bearing real estate. It includes 7km of the Garden Well trend, 11km of the Rosemont trend and 8km of the Erlistoun trend - key structural corridors that host major gold deposits elsewhere in the belt.
The latest 18 holes have delivered a standout 4m at 11.38 grams per tonne (g/t) gold from 45m, including 1m at 29.71g/t. Another hole returned 9m at 3.36g/t from 127m, including 4m at 6.77g/t, while other notable hits featured 2m at 7.27g/t from 70m and 3m at 3.88g/t from 60m.
All reported intervals are downhole lengths, with true widths yet to be confirmed. The assays have extended known mineralisation by up to 50m down-dip and identified high-grade mineralisation in previously undrilled sections.
Across Golden Boulder, mineralisation has been traced along three parallel trends called the Main Line, Eastern Line and Ogilvies. Drilling has intersected multiple stacked quartz-vein lodes with disseminated sulphides, including pyrite and arsenopyrite, hosted in basalt and minor dolerite. The company is testing whether this network of steep gold-bearing structures continues below and between the shallow workings.
The results also reinforce the prospect’s continuity. All but four of the 38 holes reported to date from the current RC program have returned mineralised intercepts grading above 0.7g/t gold, a pattern management says points to a prolific gold-bearing structural trend rather than a collection of isolated hits.
Great Southern Mining managing director Matthew Keane said: “These latest high-grade intercepts, in conjunction with previous results from 2025 and 2026 drilling, show that Golden Boulder is a high-grade gold discovery, mineralised from surface with continuity of mineralisation along ~1.1km of the 3.5km trend.”
The company expects to complete the current campaign by mid-to-late October before immediately rolling into another phase of drilling. Material step-outs at depth will be the focus, targeting extensions below an area that remains virtually untested, with few holes extending beyond 150m below surface.
Assays are pending for another 3425m from 39 holes at Golden Boulder, covering much of the remaining 2.5km of the Main Line trend. A further 2248m from 18 RC holes is awaiting results at Amy Clarke, an emerging discovery 3km north-east of Golden Boulder where shallow mineralisation has been traced across 4.7km.
The Golden Boulder area is steeped in history, with more than 50 mine shafts left by old-timers dotted across a 3.7km strike length. Old-timers reportedly pulled out 1761 ounces of gold from 1915 tonnes of ore between 1900 and 1955 at a remarkable average grade of 28.6g/t.
Golden Boulder is one of several Duketon targets Great Southern is testing as it builds a broader gold inventory. Amy Clarke is another emerging discovery, while Goldfinger is an additional target within the company’s 100 per cent-owned holding.
Nearby, Regis Resources has defined more than 7.5 million ounces just north of Great Southern’s tenure, including the two-million-ounce Rosemont deposit and the five-million-ounce Garden Well mine. Golden Boulder sits 26km from Rosemont and 14km from Regis’ Garden Well mine and processing facility. With gold commanding around US$4142 (A$5943) an ounce, a sizeable system near established roads and processing infrastructure could carry real strategic weight if drilling confirms its scale.
With high-grade gold consistently being hit from surface and a 3.5km mineralised corridor wide open at depth, Golden Boulder has plenty of room to grow. Upcoming assays and the next phase of drilling could now determine whether it can earn its place as a genuine Duketon gold system.
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