Deep Gold Hit Lifts Mulga Bill Story

Highlights

• Great Boulder Resources reports visible gold at depth at Mulga Bill

• Side Well drilling continues to expand the interpreted gold system

• Updated mineral resource estimate expected to follow ongoing work

Great Boulder Resources has intersected visible gold at depth at Mulga Bill, reinforcing the scale of the Side Well Gold Project near Meekatharra and guiding the next phase of resource growth work.

Gold exploration across Western Australia continues to attract strong attention as explorers refine targets and test deeper parts of established systems. Great Boulder Resources (ASX:GBR) has added fresh interest to this narrative after intersecting visible gold in a brecciated quartz vein at Mulga Bill, part of the company’s flagship Side Well Gold Project near Meekatharra. The latest drilling underscores the expanding scale of the Mulga Bill system and has drawn focus to the way deeper structures may influence future resource growth across the broader Side Well camp.

Mulga Bill has already built a reputation as a high-grade lode hosted system, and the latest phase of drilling is aimed at assessing how far mineralisation extends beneath earlier reverse circulation and diamond drilling. The newly reported intersection, showing coarse visible gold within a brecciated quartz vein, comes from a deep diamond hole positioned well below earlier work. This success adds a new dimension to the understanding of Side Well, shifting attention from near-surface coverage towards the deeper structural framework that may sustain long-life mineralisation.

With drilling continuing and an updated mineral resource estimate on the horizon, Side Well remains central to Great Boulder’s growth ambitions. The project’s location near an established gold mining centre, supported by existing infrastructure and services, adds further relevance as the company steps up its exploration programs and refines geological models that link Mulga Bill to nearby prospects such as Eaglehawk.

Within the broader field of ASX mining stocks, Side Well offers an example of how systematic drilling, structural interpretation and careful targeting can reveal new depth extensions beneath historically tested zones.

What stands out about the latest visible gold intersection at Mulga Bill?

The headline development from Great Boulder’s update is the identification of coarse visible gold in a brecciated quartz vein from recent diamond drilling at Mulga Bill. The relevant hole was designed to probe well below previous intercepts, stepping down into the deeper parts of the Mulga Bill system to test the continuity of mineralisation beneath earlier high-grade zones.

Geologists logging the core observed coarse specks of gold within a fractured and brecciated quartz vein, set within a broader halo of alteration and sulphide mineralisation. This style of mineralisation aligns with previous high-grade zones encountered in shallower drilling, where gold occurs in structurally focused quartz veins that exploit pre-existing fracture networks and shear zones. The fact that similar textures and mineral assemblages now appear at significantly greater depth is highly encouraging for the interpretation of Mulga Bill as a robust lode system rather than a shallow, isolated occurrence.

The company has characterised these deeper intersections as part of a high-grade structure within the broader Mulga Bill – Eaglehawk corridor. By successfully targeting the deeper extension of this structure, the drilling has reinforced the concept that the gold system continues well beneath earlier resource outlines, providing new directions for follow-up holes and ongoing modelling.

How does this drilling program test the larger Mulga Bill – Eaglehawk corridor?

The current campaign at Side Well forms part of a broader strategy to understand the full vertical and lateral extent of the Mulga Bill – Eaglehawk corridor. Earlier programs demonstrated that the corridor hosts multiple lodes and splays, with variable vein orientations and localised high-grade shoots. The latest diamond drilling adds a crucial third dimension by probing well below earlier reverse circulation and diamond holes.

The program has been designed as a staged series of holes, moving progressively along strike and down dip to test:

• The continuity of high-grade shoots at depth

• The geometry of brecciated quartz veins and associated alteration zones

• The influence of key structures on the distribution of gold within the system

By collecting oriented core, the team can refine structural interpretations, map vein orientations more accurately and identify preferred fluid pathways. This information is vital for targeting future holes towards positions where high-grade shoots may repeat or thicken. The visible gold intersection reported in the latest hole therefore serves as both a geological marker and a guidepost for further work along the Mulga Bill – Eaglehawk trend.

Why is depth extension so important for the Mulga Bill narrative?

For any lode gold system, confirmation that mineralisation continues at depth can significantly influence long-term development concepts. Near-surface mineralisation may lend itself to open pit scenarios, while deeper high-grade structures can underpin potential underground opportunities in future planning.

At Mulga Bill, earlier drilling already demonstrated strong grade characteristics in the upper parts of the system. The newly reported visible gold at depth shows that similar lode styles persist well below those earlier intercepts. This indicates that the system has vertical scale and that high-grade veins are not confined to a narrow elevation range. Such depth extension can support concepts involving staged development over time, beginning with near-surface material and potentially transitioning to deeper zones if future studies justify that pathway.

Depth continuity also plays a key role in resource modelling. When high-grade shoots can be traced over significant vertical ranges, geologists gain greater confidence in extrapolating mineralisation between pierce points, leading to more robust resource estimates. The current drilling at Mulga Bill aims to provide exactly that type of evidence, integrating new core data with previous drilling to support the upcoming resource update.

How does Side Well fit within the Meekatharra gold province?

The Side Well Gold Project lies close to Meekatharra, one of Western Australia’s long-standing gold districts with a history of open pit and underground operations across multiple deposits. This region is recognised for its complex greenstone stratigraphy, array of shear zones and structural corridors, all of which can host plurally staged gold mineralisation.

Side Well occupies a favourable position within this broader structural network. The Mulga Bill and Eaglehawk prospects are interpreted to lie along a key corridor where deformation, fluid flow and favourable host rocks converge. This combination of geological ingredients has already generated strong intercepts in earlier drilling, and the recent visible gold at depth adds further weight to the interpretation of Side Well as a significant gold camp in its own right.

Being located in a well-established mining region offers practical benefits as well. Access to roads, power corridors, skilled service providers and a supportive regulatory framework can help streamline future stages of project evaluation. For an explorer such as Great Boulder, this means that exploration success at Side Well is supported by an operating environment familiar with gold mining activities.

What could the upcoming mineral resource update mean for Side Well?

Great Boulder has indicated that work is progressing towards an updated mineral resource estimate for the Side Well Project. Resource updates typically draw together multiple data streams, including:

• New drilling results from core and reverse circulation programs

• Improved geological and structural interpretations

• Refined understanding of mineralisation styles and grade distribution

The latest visible gold intersection at depth is likely to inform both the qualitative and quantitative aspects of the resource update. Qualitatively, it demonstrates that the gold system extends deeper than previously modelled in detail, suggesting that further resource growth may be possible through ongoing drilling. Quantitatively, assays from the new holes, once received and incorporated, will help adjust grade shells, inform variography and refine the classification of resource categories.

While the precise outcome of the update will become clear only once it is released, the continued discovery of visible gold in structurally coherent positions provides a strong geological basis for ongoing work. It also highlights the value of combining shallow and deep drilling to capture the full character of the Mulga Bill – Eaglehawk corridor.

How does Great Boulder’s broader portfolio support its exploration strategy?

Great Boulder Resources is not solely focused on gold at Side Well; the company also maintains interests in base metals and other commodities across Western Australia. This broader portfolio allows it to balance exploration exposure across multiple metals while retaining a clear flagship project in Side Well.

A diversified project base can help an explorer adjust its focus as commodity markets evolve, while still ensuring that key assets receive the drilling and evaluation required to advance them through the exploration pipeline. At present, Side Well remains central due to the combination of high-grade gold intercepts, depth extension and strong geological context. The latest visible gold at Mulga Bill further reinforces that emphasis, positioning Side Well as a core narrative within the company’s overall strategy.

For market observers following trends across the ASX stock market, this blend of flagship gold exposure and additional project options offers an illustrative case of how exploration companies aim to create multiple avenues for future growth.

How does Side Well sit alongside larger ASX gold and resources names?

Within the Australian market, large and mid-cap miners often feature in benchmarks such as the ASX 100 and the ASX ordinaries stocks. These indices encompass established gold producers, diversified resource houses and broader industrial leaders. Explorers like Great Boulder sit further along the growth spectrum, focused on discovery, resource definition and early-stage evaluation rather than mature production profiles.

This contrast does not diminish the importance of exploration success. Many of the larger names in these indices have grown over time through discoveries, project acquisitions and sustained exploration. Projects such as Side Well represent the earlier stages of that lifecycle, where drilling results, resource updates and evolving geological models drive the story. For income-oriented observers who follow ASX dividend stocks, early-stage explorers may occupy a different role, often aligning with growth and discovery themes rather than regular income streams.

In this context, Great Boulder’s work at Mulga Bill contributes to the pipeline of projects that may, over time and if subsequent stages are successful, feed into broader sector development.

What are the next steps for Great Boulder at Mulga Bill and Side Well?

With drilling still underway, several key tasks lie ahead for Great Boulder at Side Well. In the near term, the company will continue to:

• Complete the remaining holes in the current diamond and reverse circulation program

• Log, sample and dispatch core for laboratory analysis

• Refine structural interpretations based on new data, particularly around the deeper visible gold intersection

• Integrate fresh results into the evolving resource model that underpins the upcoming mineral resource estimate

Beyond the immediate program, Great Boulder is likely to use the updated resource and structural insights to plan further drilling along the Mulga Bill – Eaglehawk corridor and across other targets at Side Well. Follow-up programs may focus on extending known lodes, testing parallel structures or exploring under-explored parts of the project area highlighted by geophysics and geochemistry.

As this work progresses, Side Well will remain a key reference point for those tracking how exploration success in Western Australia translates into expanding resource bases and, in time, potential development studies.