Golden Boulder Drilling Uncovers Shallow High-Grade Gold Continuity

Golden Boulder – A Promising Gold Discovery in a Prolific Region

Great Southern Mining Limited (ASX – GSN) has released encouraging initial assay results from its late-2025 reverse circulation (RC) drilling program at the Golden Boulder discovery, part of its 100% owned Duketon Gold Project in Western Australia. Situated strategically between Regis Resources’ multi-million-ounce Duketon deposits and Genesis Minerals’ Laverton tenure, Golden Boulder is emerging as a significant gold target within a prolific gold-producing belt.

The recent drilling focused on the northern 650 metres of a 3.7-kilometre prospective strike length, delivering shallow, high-grade gold intercepts that reinforce the continuity of mineralisation. Highlights include 6 metres at 6.7 grams per tonne (g/t) gold from 48 metres depth, with a standout 1 metre at 34.5 g/t, and 5 metres at 5.1 g/t from 25 metres, including 1 metre at 23.9 g/t. These results build on previous drilling successes and extend known mineralised lodes within the northern portion of the trend.

Expanding the Resource Footprint

The 56-hole RC program, completed in December 2025, was designed with three key objectives – to infill and extend mineralisation towards a maiden JORC Mineral Resource in the north, to extend mineralisation southwards where historic drilling is sparse, and to test the southernmost strike extent incorporating structural targets identified by geophysics. Assays for the remaining 29 holes, predominantly in the southern area where drilling has been limited, are expected by mid-February 2026. This southern zone remains open for further mineralisation, presenting an exciting exploration upside.

Golden Boulder’s mineralisation is hosted within fractionated dolerite rocks along the Rosemont Fault Zone, with stacked gold-bearing lodes plunging gently southwards. The shallow nature of the mineralisation is particularly encouraging for potential mining scenarios, reducing development complexity and costs.

Supporting Exploration at Amy Clarke and Future Plans

Alongside Golden Boulder, Great Southern Mining reported final assay results from the Amy Clarke prospect, where a large aircore drilling program defined gold mineralisation over a 4.5-kilometre strike. While the latest holes did not return significant new intercepts, the prospect remains a focus for upcoming RC drilling in 2026.

Looking ahead, drilling at Golden Boulder will recommence in February-March 2026, incorporating deep diamond drilling to test mineralisation at depth, alongside further RC drilling to extend strike and depth. Notably, the diamond drilling will be co-funded by the Western Australian Government’s Exploration Incentive Scheme, underscoring the project’s regional significance and potential.

Managing Director Matthew Keane expressed optimism about the results, highlighting the strong start to the program and the prospect’s location amidst established gold mines. The continuity of shallow, high-grade mineralisation bodes well for advancing Golden Boulder towards resource definition and eventual development.