Assays from the first 19 holes, covering 2,436 metres of a planned 14,000‑metre RC program, revealed mineralised intercepts in every hole except one, all above the 0.7 g/t threshold. The standout result was a 10‑metre interval averaging 2.62 g/t gold from 20 metres depth, which included a 2‑metre sub‑interval of 10.72 g/t and a 1‑metre section of 2.20 g/t.
Other notable hits included an 8‑metre interval grading 2.24 g/t from 102 metres (with 2 metres at 7.20 g/t) and a 7‑metre interval of 2.45 g/t from 41 metres that contained a 1‑metre stretch of 6.91 g/t. Deeper sections returned 3‑metre intervals of 3.07 g/t at 105 metres and 3.32 g/t at 121 metres, plus a 4‑metre interval of 1.85 g/t from 145 metres that featured a 1‑metre high of 6.62 g/t.
The drilling campaign is focused on the northern 450‑metre segment of Golden Boulder’s 3.5‑km Main Line trend, one of three parallel mineralised corridors that also include the Eastern Line and Ogilvies prospects. A further 48 holes, representing 5,428 metres of completed drilling from the Main and Eastern Lines, are awaiting assay results.
Golden Boulder sits on a historic goldfield that saw 1,915 tonnes of ore mined at an average 28.6 g/t between 1900 and 1955, yielding 1,761 ounces of gold. Modern exploration in 2025 previously intersected 5 metres at 14.6 g/t from 41 metres, including a 1‑metre spike of 70.9 g/t, underscoring the area’s high‑grade potential.
Managing Director Matthew Keane said the new data “support our view that Golden Boulder and the wider Duketon Gold Project have potential for significant scale” and highlighted the continuity of high grades from the shallow oxide zone into underlying fresh rock. He added that the results suggest the possibility of multiple open‑pit operations within 20 kilometres of existing gold‑processing facilities.
Interpretation work is under way to model the stacked quartz‑vein lodes that host pyrite and arsenopyrite within basalt and minor dolerite. The company will assess the growing RC dataset before planning follow‑up drilling, and a formal resource estimate could be prepared once the data are fully interpreted.
In parallel, assays from the Amy Clarke discovery, located 3 km northeast of Golden Boulder, are pending. That RC program comprised 18 holes and 2,248 metres and has already defined mineralisation across a 4.7‑km strike.
Golden Boulder’s geological setting aligns with the structure that hosts Regis Resources’ Rosemont deposit, a >2‑million‑ounce gold resource 26 km away that extends beyond 700 metres depth. The Duketon district also lies between Regis’ 12‑million‑ounce Duketon camp and Genesis Minerals’ 6‑million‑ounce Laverton tenure, reinforcing the region’s status as a prolific gold province.
Great Southern’s broader portfolio includes the Mt Dillon copper‑gold target in Queensland’s Edinburgh Park project, where diamond drilling has recently concluded and core processing is underway. A strategic agreement with Gold Fields allows the latter to fund up to 75 percent of a $15 million exploration spend, giving Great Southern exposure to the Queensland asset while it concentrates resources on its Western Australian gold assets.