Great Southern Mining Reports Strong Drilling Results North of Mon Ami Deposit
Great Southern Mining (ASX: GSN) has reported assay results from the first six holes of a 16-hole reverse circulation drilling program at its 100%-owned Mon Ami Gold Project in Western Australia. The Great Southern Mining Mon Ami gold drill results 16m at 3.37 g/t Au headline a set of findings that extend known mineralisation up to 70 metres down dip and 55 metres down plunge beyond the existing resource boundary, including a higher-grade section of 4 metres at 8.54 g/t gold.
Ten further holes remain to be assayed at the Blanc Platt target north of the existing resource, while additional drilling programs continue at two other GSN projects, pointing to a sustained period of news flow for the company.
Managing Director Matthew Keane commented: "These first set of results highlight the potential for substantial growth to the Mon Ami Resource. These intercepts represent significant extensions beyond the known mineralisation. Excitingly, we have more assays pending and the mineralisation remains open. With this being really the first campaign at Mon Ami to understand the potential at depth, it is very exciting that we are seeing wide zones of higher grade opening up at depth."
The six reported holes form part of a broader 16-hole, 3,089-metre RC program designed to test two targets: depth extensions to the existing resource and a possible northern offset lode at Blanc Platt. According to the announcement, the first six holes focused entirely on down-dip and down-plunge extensions to known mineralisation.
| Hole ID | Significant Intercept | Grade (Au g/t) | Depth From | Extension Achieved |
|---|---|---|---|---|
| 26MARC001 | 16m | 3.37 g/t (incl. 4m at 8.54 g/t) | 178m | 45m below prior intercepts |
| 26MARC001 | 4m | 1.45 g/t | 202m | Same hole, deeper zone |
| 26MARC002 | 15m | 1.31 g/t | 221m | 60m below prior intercepts |
| 26MARC002 | 1m | 7.53 g/t | 147m | High-grade hit, shallower |
| 26MARC004 | 16m | 1.28 g/t | 281m | 30m below historic hole |
| 26MARC004 | 6m | 1.83 g/t (incl. 1m at 7.28 g/t) | 150m | – |
| 26MARC005 | 7m | 1.52 g/t | 205m | – |
| 26MARC006 | 19m | 1.12 g/t (incl. 1m at 5.00 g/t) | 213m | 55m down plunge to north |
The results point to consistency of mineralisation across multiple holes, alongside indications of higher-grade zones at depth. Furthermore, Hole 26MARC006 is described in the announcement as opening a "significant new target area for future drilling," with its 19-metre intercept extending mineralisation 55 metres down plunge to the north.
For readers less familiar with gold exploration geology, some context on Mon Ami's structural setting is useful.
A shear zone is a corridor of intense geological deformation — essentially a zone where rocks have been stressed and displaced along a fault system over long periods. These zones are important hosts for gold mineralisation because fluid movement through fractured rock tends to concentrate gold-bearing minerals along defined pathways.
Mon Ami sits on the Barnicoat Shear Zone (BSZ), which defines the eastern flank of the central terrain of the Laverton Tectonic Zone in Western Australia, a historically significant gold-producing region. The BSZ also hosts the Ida H mine, located approximately 8 kilometres north along the same structural corridor and owned by Genesis Minerals.
Historical underground production at Ida H totalled 229,900 tonnes at 22.6 g/t gold for 170,650 ounces in the early 1900s. The announcement describes Ida H as the closest geological analogue for Mon Ami's depth potential, which consequently makes these depth extension results particularly noteworthy.
Mon Ami currently holds a JORC (2012) Mineral Resource of 1.56 Mt at 1.11 g/t gold for 55,500 ounces, underpinned by an Indicated Resource of 1.41 Mt at 1.16 g/t gold for 52,500 ounces.
| Classification | Cut-off Grade | Tonnage | Grade | Gold (oz) |
|---|---|---|---|---|
| Indicated | 0.5 g/t Au | 1.41 Mt | 1.16 g/t | 52,500 oz |
| Inferred | 0.5 g/t Au | 0.15 Mt | 0.61 g/t | 3,000 oz |
| Total | 0.5 g/t Au | 1.56 Mt | 1.11 g/t | 55,500 oz |
This resource estimate dates from July 2021, meaning the current program represents the company's first systematic attempt to test the deposit's depth potential. According to the announcement, mineralisation remains open down-dip to the west, vertically at depth, and down-plunge to the north.
In addition, the company has indicated that an updated Mineral Resource Estimate will likely be completed in the future as further drilling results are received, which could significantly alter the overall picture for the project.
Beyond exploration results, Mon Ami is located on a granted Mining Licence (M 38/1256), with a Special Licence for a haulage route to the Elora-Mount Weld sealed road already granted. According to the announcement, several studies prerequisite for a mining operation have already been completed, including:
The project is located 12km south of Laverton and approximately 12km east of the Granny Smith gold processing facility, within a 50km trucking radius of multiple operating and planned gold processing facilities in the Laverton district. The company has stated that this proximity supports its consideration of Mon Ami as a potential near-term development opportunity, though any development pathway would remain subject to further studies and approvals.
GSN's drilling activity extends beyond Mon Ami, with several catalysts expected across its project portfolio in the coming weeks and months.
| Catalyst | Timeline | Project |
|---|---|---|
| Assay results, 10 holes at Blanc Platt target | 1–2 weeks | Mon Ami Gold Project |
| Assay results, 38 holes (4,726m) at Golden Boulder discovery | Coming weeks | Duketon Gold Project |
| Ongoing RC drilling results, Amy Clarke discovery | Ongoing | Duketon Gold Project |
| Ongoing diamond drilling results, Mt Dillon target (JV with Goldfields) | Ongoing | Edinburgh Park Project, Queensland |
| Updated Mineral Resource Estimate for Mon Ami | Future, timing to be confirmed | Mon Ami Gold Project |
The Blanc Platt target, situated north of the existing Mon Ami resource, is of particular interest following a 2025 aircore program that intersected 2 metres at 1.86 g/t gold from 20 metres depth. Ten RC holes have now been completed at this target, with assays pending and expected within one to two weeks according to the company.
Several factors from the announcement are relevant to how investors might assess GSN's current position.
Resource growth potential: The Great Southern Mining Mon Ami gold drill results 16m at 3.37 g/t Au suggest the existing 55,500-ounce resource may not reflect the full extent of mineralisation at depth. With mineralisation open in multiple directions and higher-grade zones identified at depth, alongside the geological analogue presented by the nearby Ida H deposit, further resource growth may be possible pending additional drilling and updated estimates.
Permitting progress: A granted Mining Licence combined with completed environmental, heritage, and metallurgical studies places Mon Ami at a more advanced permitting stage than many exploration-stage projects.
Location within an established gold district: Proximity to multiple gold processing facilities within a 50km radius may support toll-treatment options, which the company suggests could reduce the capital requirements typically associated with standalone processing infrastructure.
Diversified news flow: With drilling activity concurrently underway at Mon Ami, the Duketon Gold Project (Golden Boulder and Amy Clarke), and the Edinburgh Park Project in Queensland (in joint venture with Goldfields), GSN's newsflow is not limited to a single asset or drilling campaign.
The Great Southern Mining Mon Ami gold drill results 16m at 3.37 g/t Au extend known mineralisation well beyond the current resource boundary, representing a meaningful step forward for the project. With assay results pending from Blanc Platt and two additional projects active, and a resource update flagged as a future possibility, the company's drilling pipeline is set to generate further updates over the coming weeks and months.
Assay results from the remaining ten holes at Blanc Platt are expected within one to two weeks, while results from the 38-hole program at Golden Boulder are anticipated in the coming weeks. Investors monitoring GSN's progress will likely focus on whether these upcoming results continue the pattern of extension and higher-grade intercepts established in this initial batch of assays.
Great Southern Mining (ASX: GSN) is advancing a high-potential gold portfolio in Western Australia, with depth extensions at Mon Ami, a pipeline of pending assay results, and drilling activity across multiple projects. For investors looking to understand the full scope of the company's projects, resource potential, and upcoming catalysts, head to the Great Southern Mining website to find out more.