Horizon Gold Drills High-Grade Gold at Gum Creek, Expanding Resource Base

Horizon Gold Drills Shallow High-Grade Gold Outside Study Scope at Gum Creek

Horizon Gold Limited (ASX: HRN) has reported a new set of reverse circulation drilling results from its 100% owned Gum Creek Gold Project in Western Australia, with high-grade gold intercepts returned from Swift, Eagle, Goldfinch and Shrike South. According to the ASX announcement, the latest assays support resource growth across multiple deposits as the company advances its Feasibility Study (FS) toward a mid-2026 release.

The update is important because several of the strongest results sit outside the current FS resource base. Horizon said resource estimation is underway at Eagle, while maiden Mineral Resource Estimates (MREs) are planned for Goldfinch and Shrike South, creating a pathway for additions beyond the company's current 2.30-million-ounce project resource.

"These impressive high-grade RC drilling results from Swift, Eagle, Shrike South and Goldfinch continue to unlock our free-milling open pit mining strategy. We're consistently adding shallow, high-grade resource ounces less than two kilometres from the proposed 2.4Mtpa processing plant while simultaneously drilling deeper to unlock the underground potential throughout the Gum Creek Greenstone Belt."

— Scott Williamson, Managing Director

What the Latest Gum Creek Drilling Update Showed

The drilling results cover six prospects in total: Swift, Eagle, Goldfinch, Shrike South, Thornbill West and Vigilant. The strongest investor focus was on the first four, where Horizon reported consistent shallow and, in some areas, higher-grade mineralisation close to the historic Gidgee Mill and proposed 2.4Mtpa processing plant.

Across the programme, the company completed more than 6,500 metres of RC drilling, with each deposit contributing a different part of the development picture. Some targets are being drilled to extend existing resources, while others are moving toward a first formal estimate.

Swift Drilling: Does It Support Extensions Outside the Current Model?

The Swift Prospect, located 1.2km east of the historic Gidgee Mill, already contains a substantial resource. Horizon's current Swan/Swift open cut MRE stands at 7.00Mt @ 1.85g/t Au for 415,600oz, while the Swift underground MRE stands at 0.85Mt @ 2.52g/t Au for 68,800oz.

Horizon completed 12 RC holes for 1,974m, including three pre-collars for diamond drilling. The programme targeted down-dip and up-dip extensions to high-grade mineralisation outside the existing resource block model.

Key reported intercepts at Swift included:

According to the announcement, these results support a flat-lying stacked lode model west of the main Swift lode. Furthermore, the SFRC002 intercept sits 40m down-dip from previous drilling and will require additional work.

Diamond core extensions to three RC pre-collars are planned to test the main lode at depth, with Horizon targeting a Swift MRE upgrade later in 2026.

Eagle Drilling: How Far Has Mineralisation Extended?

The Eagle Prospect, located 1.2km southeast of the Gidgee Mill, has a current MRE of 2.02Mt @ 1.28g/t Au for 83,400oz. In this campaign, Horizon drilled 33 RC holes for 2,590m to test shallow mineralisation along strike from the existing resource.

Notably, drilling has extended known gold mineralisation by approximately 300m to the south of the current block model. That extension is central to the next Eagle resource update.

Key Eagle intercepts included:

The announcement described mineralisation at Eagle to about 70m below surface as supergene related, meaning the gold has been enriched near surface by weathering processes. For investors, such material is often targeted early in open pit mine plans due to its shallow depth. Wireframing is now underway ahead of an updated Eagle MRE.

Goldfinch Moves Toward a Maiden Resource Estimate

Goldfinch is located 2.0km southeast of the Gidgee Mill and does not yet have a formal resource estimate. Horizon drilled two RC holes for 170m, including one re-entry extension, as follow-up to drilling completed in late 2025.

Both reported holes returned strong grades:

Geological wireframing is underway ahead of deeper drilling and the estimate of a maiden MRE. For a prospect with no current resource, two intercepts above 5 g/t Au are particularly relevant because they may help establish an initial resource shell if continuity is confirmed by further drilling.

Shrike South Adds Another Near-Mill Growth Area

The Shrike South Prospect, 1.3km southeast of the Gidgee Mill, has been historically mined by open cut methods across about 280m of strike but is not included in Horizon's current project-wide resource estimate. The latest programme comprised 12 RC holes for 1,187m, testing shallow extensions beneath and along strike of the existing pit.

Key Shrike South intercepts included:

According to the ASX release, wireframing is underway for a maiden MRE, and metallurgical sampling plus gravity/cyanide leach test work is planned in coming months. In practical terms, that test work is designed to assess how efficiently gold can be recovered using standard processing methods.

Why MRE Updates Matter in Gold Development

A Mineral Resource Estimate (MRE) is a formal calculation of how much gold is believed to be present in the ground, at what grade, and with what level of confidence. Under the JORC Code, resources are grouped into categories such as Indicated and Inferred, depending on drilling density and geological confidence.

An MRE is one of the core inputs used in mine studies. It influences a range of key factors, including:

• Mine life assumptions
• Open pit and underground designs
• Production scheduling
• Processing plant utilisation
• Project valuation in studies such as scoping, pre-feasibility and feasibility work

At Gum Creek, the distinction is especially relevant because results from Eagle, Goldfinch and Shrike South sit outside the current FS scope. If those prospects are converted into larger or new resources, they may offer future mine plan flexibility or economic upside beyond the first version of the study.

Key Technical Terms Explained

• RC drilling: A fast drilling method that brings rock chips to surface for sampling, commonly used for shallow to medium-depth gold exploration.
• g/t Au: Grams of gold per tonne of rock — the standard way gold grade is reported.
• Supergene mineralisation: Gold enriched near surface by weathering, often shallower than the original hard-rock source.
• Wireframing: Building a 3D geological shape of mineralised zones before estimating tonnage and grade.
• JORC Code: The Australian reporting standard used for mineral resources and ore reserves on the ASX.

The Existing Gum Creek Resource Base Already Provides Scale

Horizon's existing project-wide MRE at Gum Creek stands at 37.97Mt @ 1.89g/t Au for 2,301,600oz, with 71% of ounces in the higher-confidence Indicated category.

A snapshot of key current resources includes:

This existing inventory means Horizon is not relying on a single discovery area. Instead, the ASX update points to a multi-deposit development case, with potential additions from prospects located close to planned infrastructure.

What the Feasibility Study Progress Means for Investors

In the announcement, Horizon confirmed the Gum Creek Feasibility Study is progressing well, with risk assessments concluded and a draft report nearing completion. The study remains on schedule for a mid-2026 release.

The company also stated that preparation work for the Mine Development and Closure Proposal (MDCP) and associated statutory applications is underway. This indicates that technical and permitting-related workstreams are being advanced in parallel, however the announcement does not state that approvals have been granted.

For investors, the key point is timing. The FS is the main development milestone, but near-term resource updates may continue to change the broader project picture both before and after the study is published.

Near-Term Catalysts to Watch at Horizon Gold

According to the current update, the next milestones include:

1. Eagle MRE update, following the 300m southern extension
2. Goldfinch maiden MRE, supported by current wireframing and further drilling
3. Shrike South maiden MRE, with metallurgical work also planned
4. Swift diamond drilling, ahead of a later 2026 MRE upgrade
5. Mid-2026 Feasibility Study release
6. Ongoing MDCP preparation work

These catalysts matter because they combine both resource growth and development progression — the two main drivers of value for many pre-production gold companies.

Why the Gum Creek Update Is Relevant for ASX Gold Investors

The latest drilling update from Horizon Gold points to a project being advanced on several fronts simultaneously. The reported results support extensions at existing resources, add momentum toward maiden resources at previously unmodelled deposits, and continue to build the case for shallow ore sources near the proposed processing hub.

Several factors stand out from the announcement:

• Shallow mineralisation at Eagle, Goldfinch and Shrike South aligns with an open pit development focus
• High-grade intercepts such as 17.6 g/t Au at Swift and 16.35 g/t Au at Eagle may support local grade strength within broader resource zones
• Close proximity to the proposed plant site may be relevant for future haulage and development assumptions
• New resource work sits outside the current FS scope, potentially leaving room for later study or mine plan improvements

The ASX update does not yet quantify how many additional ounces may come from Eagle, Goldfinch or Shrike South. That remains dependent on wireframing, further drilling and formal resource work. Even so, the Horizon Gold Gum Creek drilling results indicate that the project's resource base may continue to expand as the company moves toward its next major study milestone.

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