Redcastle Resources Diamond Drilling Validates RR–QA Gold Systems

Redcastle Resources Drills Into Confidence: Diamond Programme Validates Gold System Ahead of Near-Term Mining

Redcastle Resources Limited (ASX: RC1) has delivered a five-hole diamond drilling programme across its Redcastle Reef (RR) and Queen Alexandra (QA) gold deposits in Western Australia's Eastern Goldfields, and the Redcastle Resources diamond drilling results at Redcastle Reef and Queen Alexandra gold deposits reinforce geological confidence in both deposits whilst supporting the company's near-term development pathway. The programme, completed by joint venture partner BML Ventures Ltd on behalf of the Redcastle–BML Joint Venture, was designed not as a discovery exercise but as a targeted geological confirmation campaign — one that is directly feeding mine planning, ore delineation and operational execution.

The headline results speak for themselves. At Redcastle Reef, drill hole 26RRDD003 returned 23.13m @ 1.83 g/t Au from 21m, including a higher-grade interval of 14m @ 2.73 g/t Au, with a peak of 1m @ 29.0 g/t Au. At Queen Alexandra, 26QADD002 intersected 2m @ 5.49 g/t Au from 21m in the Kestrel Lode, including 0.5m @ 9.54 g/t Au, along with a separate intercept in the Hawk Lode at depth — a result that points to the mineralised system extending well beyond the current pit boundaries.

"This diamond core programme reinforces our confidence in the RR–QA short-term development pathway. The core intersections of the Kestrel and Hawk Lodes at QA have already verified RC1's original pre-drill interpretation. Within the context of the BML JV and the Company's capital-light structure, we are now seeing the key elements — geology, approvals and development — coalescing toward the reality of near-term mining." — Chairman Dr Ray Shaw

All Five Holes Return Mineralisation: The Full Results at a Glance

Every hole in the programme intersected gold mineralisation, providing a consistent picture of a geologically coherent system across both deposits. The table below summarises the significant intercepts (≥1.0 g/t Au) from the campaign.

All values are uncut. Intercepts are reported as downhole lengths; true widths have not yet been determined. Note that 26RRDD003 was deliberately drilled down the interpreted mineralised structure to test down-dip continuity and the reported interval does not represent a true width.

At Redcastle Reef, the three holes collectively demonstrate broad, shallow mineralisation sitting comfortably within the 2025 Mineral Resource Estimate (MRE) conceptual pit area. The mineralisation model — quartz veining, quartz–iron oxide stringers and altered wall-rock zones — has been directly confirmed through core observation, adding a layer of geological confidence that RC drilling programmes alone could not deliver.

Understanding Diamond Drilling: Why Core Matters More Than Chips?

Reverse Circulation (RC) drilling is the workhorse of exploration programmes. It operates by using compressed air to force rock cuttings up through a dual-wall pipe system, producing rock chip samples from which grades can be estimated. RC drilling is fast and cost-effective, making it ideal for resource definition and initial exploration work.

Diamond drilling, however, uses a rotating drill bit studded with industrial diamonds to cut through rock and retrieve a continuous cylinder of intact core, typically around 45–65mm in diameter. This core can be physically handled, photographed, logged in detail and structurally measured.

What Are the Critical Differences for Mining Development?

• Geological Intelligence: Diamond core allows geologists to directly observe mineralisation controls — the exact structures, alteration zones and vein orientations that host gold. RC chips cannot provide this level of structural detail.

• Mining Precision: Core enables precise measurement of where ore ends and waste begins, which is critical for selective mining and grade control during actual operations.

• Structural Analysis: Oriented core provides direct measurements of structural orientations, fault systems and vein attitudes that feed directly into geological models and pit designs.

• Resource Confidence: Diamond drilling provides the geological confidence required to support mine planning and operational execution, rather than just resource estimation.

The diamond core programme at RC1 was not designed to discover new gold — it was designed to understand the gold already identified well enough to mine it accurately and efficiently. This represents a significant shift from exploration to development-focused drilling.

Redcastle Reef: Broad, Shallow Gold Confirmed Within the Pit Shell

The three Redcastle Reef holes confirm that mineralisation sits within the existing 2025 MRE conceptual pit shell at shallow depths — the shallowest significant intercept beginning at just 18m downhole in 26RRDD002 (15m @ 1.94 g/t Au). This proximity to surface is operationally significant, reducing the strip ratio required to access ore early in any mining sequence.

Key observations from the RR programme include:

• Geological Validation: Mineralisation is associated with main quartz veining, quartz–iron oxide stringers and altered wall-rock zones, directly matching the existing geological model established through previous drilling.

• Spatial Continuity: Broad mineralised intervals across three separate sections demonstrate lateral and down-dip continuity within the planned pit area.

• Grade Variability: The 1m @ 29.0 g/t Au peak interval within 26RRDD003 highlights the presence of higher-grade zones within the broader mineralised envelope — zones that grade control can specifically target during mining operations.

Furthermore, the RR diamond drilling follows the recently completed RR grade-control drilling programme and the Mining Development and Closure Proposal (MDCP) approval, meaning the deposit is progressively being characterised at the level of detail required for actual mining operations rather than conceptual studies.

Queen Alexandra: Multi-Lode System Reaches Deeper Than the Current Pit

The two Queen Alexandra holes are arguably the most strategically significant results in this programme from a resource growth perspective. Whilst the intercepts themselves are narrower and higher-grade, consistent with a shear-hosted lode system, the critical observation is the depth at which mineralisation was encountered.

26QADD002 intersected the Kestrel Lode at shallow depth (2m @ 5.49 g/t Au from 21m) and the Hawk Lode at 81.5m downhole (1.5m @ 1.49 g/t Au) — a depth that sits below and beyond the current 2025 MRE conceptual pit shell. This supports the interpretation that the QA lode system has potential to extend beneath the planned open pit, opening a pathway for future resource growth through targeted deeper drilling.

The QA results are consistent with a stacked, multi-lode shear-hosted gold system. In addition, the Kestrel Lode splay intercept in 26QADD001 (1m @ 2.13 g/t Au from 43m) further demonstrates the structural complexity of the system — complexity that diamond core is uniquely positioned to decode through direct structural measurement and geological observation.

Development Timeline Taking Shape: From Exploration to Mining

This diamond drilling programme sits within a rapidly accelerating development sequence for RC1. The recent announcement history illustrates a clear progression from exploration to development over a compressed timeframe.

Consequently, the company has outlined the following priorities flowing from this diamond drilling programme:

1. Integration of diamond core data into updated geological and structural interpretation
2. Refinement of pit design, ore delineation and selective mining parameters for RR-QA
3. Ongoing grade-control planning informed by core observations
4. Assessment of QA depth extensions through future targeted drilling where warranted
5. Continued technical work to support operational readiness under the Redcastle–BML Joint Venture framework

The Investment Thesis: Geology Meets Execution in the Eastern Goldfields

RC1's investment case is anchored in the convergence of three factors that rarely arrive simultaneously for a junior gold company: confirmed mineralisation, regulatory progression and a capital-light development structure.

Validated Geological Model Moving Toward Production

The Redcastle Resources diamond drilling results at Redcastle Reef and Queen Alexandra gold deposits have achieved exactly what they were designed to accomplish — confirm that the geological models underpinning both deposits are accurate. RC1 is no longer a company searching for gold; it is a company confirming where that gold sits and how best to extract it through selective mining operations.

Capital-Light Joint Venture Structure

The Redcastle–BML Joint Venture allows RC1 to advance toward production without bearing the full capital burden independently. BML Ventures completed this drilling programme on behalf of the JV, reflecting the collaborative framework through which the project is being developed.

Regulatory Progress Already Secured

The recently approved Mining Development and Closure Proposal (MDCP) represents a meaningful regulatory milestone, clearing one of the key approvals required ahead of mining commencement. This is the kind of de-risking event that can materially shift the probability-weighted value of a development-stage project.

Resource With Upside Potential

With the QA multi-lode system now demonstrating potential below the current pit shell, the existing 42,000 oz JORC-compliant resource base may not represent the full extent of the mineralised system. Any future resource growth through deeper drilling would add to the project's long-term optionality beyond the initial pit-constrained mining operation.

Eastern Goldfields Geological Setting

RC1 operates within the Archaean greenstone sequences of Western Australia's Eastern Goldfields — one of the world's most proven gold-producing regions. The geological setting is well understood, infrastructure is established, and the regulatory and technical frameworks for gold mining are mature.

Why Investors Should Monitor RC1 Closely

Redcastle Resources is positioned at a critical inflection point. The company has moved systematically through exploration, resource definition, scoping studies, grade-control drilling, regulatory approvals and now geological confirmation drilling — in a compressed and disciplined timeframe. Each step has been designed to reduce technical risk and advance the project toward mining operations.

The Redcastle Resources diamond drilling results at Redcastle Reef and Queen Alexandra gold deposits are not a standalone event. They represent the latest link in a chain of de-risking milestones, and the Chairman's comments suggest the company views near-term mining as a realistic, near-horizon outcome rather than a distant aspiration.

Key reasons to monitor RC1:

• Near-term development pathway being actively prosecuted within a capital-light JV structure
• Geological model confirmed across both RR and QA deposits through diamond core analysis
• QA depth extensions suggest resource growth potential below the current pit design
• MDCP approval secured, reducing key regulatory hurdles ahead of mining
• Eastern Goldfields tenement portfolio extending to approximately 12,875 hectares across granted and live tenures, providing long-term exploration optionality

Key Takeaway:
Redcastle Resources has positioned itself as a credible near-term gold producer in one of Australia's premier mining jurisdictions. With geology now confirmed, regulatory approvals progressing and a capital-light JV development structure in place, the key elements are converging. Investors tracking the transition from explorer to producer should monitor RC1 closely as the RR–QA development pathway advances toward operational reality.

Technical Glossary: Understanding the Mining Terms

MRE (Mineral Resource Estimate): A JORC-compliant estimate of the quantity and grade of mineralisation identified through drilling. RC1's current MRE stands at 42,000 oz gold.

g/t Au: Grams of gold per tonne of rock — the standard measure of gold grade in the mining industry.

Diamond Drilling: A drilling method that recovers intact cylindrical rock core, enabling detailed geological observation and structural measurement for mine planning.

Shear-Hosted Gold: Gold mineralisation that is structurally controlled by shear zones — fault-related deformation corridors that focus fluid flow and gold precipitation.

MDCP (Mining Development and Closure Proposal): A regulatory approval document required in Western Australia before mining activities can commence.

Down-Dip: In the direction that a geological structure inclines downward into the earth.

JORC Code: The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves — the standard for transparent and professional reporting in the Australian mining industry.

Vein-Stockwork: A network of intersecting mineralised veins hosted within a rock volume, often producing bulk-mineable gold mineralisation suitable for open-pit extraction.

Ready to Dig Deeper Into Redcastle Resources' Near-Term Gold Development?

Redcastle Resources (ASX: RC1) is advancing systematically from explorer to near-term gold producer, with geological confirmation now secured across both the Redcastle Reef and Queen Alexandra deposits. With a capital-light JV structure, key regulatory approvals in place, and a confirmed 42,000 oz JORC-compliant resource base showing further depth potential, RC1 represents a compelling development-stage opportunity in Western Australia's Eastern Goldfields. Investors seeking to understand the full scope of RC1's project pipeline, JV framework, and development pathway can explore the details at redcastle.net.au.