Boab Metals Advances Sorby Hills Reserve Expansion with 60% Completion of Phase IX Drilling and Promising Initial Outcomes

Boab Metals' Sorby Hills Project: Core Asset and Operational Backbone

Boab Metals Limited is an Australian exploration and development company focused on advancing the Sorby Hills Silver-Lead-Zinc Project situated in the onshore Bonaparte Gulf Basin, Western Australia. This project is a pivotal asset for the company, poised to become Australia's next major silver producer. Fully funded and under construction, the company is executing targeted geological and exploration activities to enhance the resource base's value.

The Sorby Hills Project includes multiple mineral deposits such as the B-Deposit, Omega-Deposit, Norton-Deposit, Beta Deposit, and the Keep Target, alongside the separate Manbarrum Project. Collectively, these deposits underpin the mine plan outlined in the feasibility (FEED) study. Its strategic location within the Bonaparte Gulf Basin offers access to established infrastructure and transport networks, supporting development timelines and operational efficiency.

Phase IX Drilling Program and Reserve Conversion Approach

Launched in May 2026, the Phase IX drilling program is designed to support both near-term production scaling and long-term value creation at Sorby Hills. It consists of three components: resource-to-reserve conversion drilling to upgrade portions of the Mineral Resource for detailed mine planning and scheduling; silver-focused resource expansion drilling targeting extensions of known mineralisation, especially silver intercepts previously excluded due to lead-only cut-off grades; and exploration drilling testing targets identified from geological interpretations and historical data.

Boab Metals clarified that reserve conversion drilling is not a prerequisite for drawing on the project finance debt facility, reflecting financial flexibility and the discretionary nature of this value-add program. The total Phase IX drilling plan covers approximately 5,000 metres, with 28 sonic and diamond core holes completed to date totaling about 3,000 metres. Drilling at the B-Deposit, Omega-Deposit, and Norton-Deposit—the primary resource areas for the FEED Study—is complete, with remaining work focused on Beta Deposit, Keep Target, and one deep hole at Manbarrum Project.

B-Deposit Drilling Outcomes and Pit Expansion Prospects

At the B-Deposit, seven holes were drilled mainly along the eastern down-dip perimeter and up-dip zones to target areas with potential positive impacts on reserve estimates and mine planning. The drilling intersected targeted mineralised horizons with metre-range accuracy against geological model boundaries, validating current interpretations. Notably, mineralisation widths exceeded those predicted by nearby intercepts, indicating potential for increased ore tonnage.

Drill hole SHSD_205 may extend mineralisation up-dip to within 20 metres of the surface, potentially improving pit design economics and operational access. Holes SHSD_203 and SHSD_204 could increase ore zone thickness at depth, possibly enlarging the pit shell and ore volume. These results are attributed to a gentle synform structure and preservation of the target horizon, suggesting the B-Deposit may contain more mineralisation than currently reflected in the FEED Study pit design, with implications for reserve growth and mine-life extension.

Omega-Deposit Mineralisation Wider Than Geological Models

At Omega-Deposit, 18 holes were drilled primarily along the eastern down-dip perimeter, testing mineralisation near the northern edge but outside the current FEED pit shell. Geological model boundaries were intersected with metre-range accuracy, confirming structural interpretations. However, mineralisation intervals often exceeded previously interpreted widths, signaling potential for resource and reserve expansion.

Positive mineralisation was observed in holes SHSD_195 (Omega South) and SHSD_214 (north). The economic impact of grade and thickness at depth will be assessed after laboratory assays. Over 860 samples from reserve conversion drilling have been submitted for analysis, with results pending. The broader-than-modelled mineralisation at Omega suggests opportunities for ore reserve conversion and mine-life extension once assay data is available.

Norton Deposit High-Grade Galena Discovery and Silver Production Potential

The Norton-Deposit drilling included three holes about 100 metres north of the current pit perimeter to test continuity of high-grade silver and lead mineralisation. Drill hole SHSD_216 intersected an exceptionally high-grade galena interval exceeding previous mineralisation models in width and grade. This high-grade zone remains open to the north, indicating potential further extensions.

Results from SHSD_216 are expected to enhance the cluster of high-grade intercepts north of the current pit, separated by a low-grade breccia zone. This discovery supports expanding the known high-grade zone and increasing silver production. The hole also confirmed patchy, silver-dominated galena mineralisation, aligning with the company’s strategy to target silver-rich extensions previously excluded due to lead-only cut-off grades. These findings support Boab’s goal of boosting silver exposure and long-term production value.

Mineralisation Extending Beyond Existing FEED Pit Designs

A key finding from Phase IX drilling is that mineralisation extends beyond FEED Study pit designs across multiple deposits. Several holes encountered mineralised intervals broader than current models, indicating potential resource and reserve growth. This pattern spans the B-Deposit, Omega-Deposit, and Norton-Deposit, the main resource zones underpinning the mine plan.

This consistency suggests the current geological model may be conservative in some areas, possibly due to historical drilling limitations or interpretation methods. Boab’s Managing Director and CEO, Simon Noon, stated, "mineralisation continues beyond areas currently incorporated within the Sorby Hills mine plan and, in a number of locations, appears broader than our existing geological model predicts." This reflects management’s confidence in material reserve upgrades as assay results emerge. Extensions beyond pit designs have direct implications for pit optimisation, reserves, mine life, and production scheduling, all critical to project economics and shareholder value.

Sample Submission and Assay Result Timeline

Boab has submitted over 860 samples from reserve conversion drilling at the B, Omega, and Norton deposits for laboratory analysis. Assay results have not yet been released; the Managing Director confirmed that "assay results are still pending" and the company anticipates "reporting assay results as they become available." Early geological observations are based on visual assessments during drilling rather than definitive assay data.

The timing of assay releases will be vital for investors tracking project progress. While visual observations offer promising preliminary insights, final reserve and resource upgrades depend on laboratory data and technical modelling. Boab intends to report results progressively, indicating it will communicate findings before all analyses are complete. The company’s commentary that these observations "provide growing confidence that the program can deliver additional Ore Reserves" signals management’s positive outlook pending assay confirmation.

Value Creation Strategy and Project Financing Context

The Phase IX drilling program is strategically aimed at capturing upside potential during the fully funded and under-construction phase of Sorby Hills. Managing Director Simon Noon remarked, "with Sorby Hills fully funded and under construction, every opportunity to add Ore Reserves, extend mine life or increase silver production has the potential to create meaningful shareholder value. This program has been specifically designed to capture that upside." This underscores management’s belief that reserve growth and mine-life extension during construction can significantly enhance project returns.

The company emphasized that reserve conversion drilling is not a condition for accessing the project finance debt facility, highlighting the discretionary and value-add nature of this work. This financial flexibility reflects confidence in the project’s economics without additional reserves. Nonetheless, investing in Phase IX drilling during construction demonstrates conviction that reserve upgrades are achievable and economically justified. Potential increases in ore reserves, mine life beyond the FEED Study, and silver production exposure position Boab to unlock further value if drilling and mine planning optimisations succeed.

Silver Production Emphasis and Resource Re-estimation Plans

Phase IX drilling includes a focus on silver-targeted resource expansion, aiming to extend known mineralisation, especially silver intercepts previously excluded due to lead-only cut-off grades. This approach recognizes silver’s premium value and that current estimates may understate the project’s silver content. The company indicated this work "may support a re-estimation of the Mineral Resource on a combined lead-silver basis and potential mine-life extensions," suggesting current estimates may omit economically valuable silver mineralisation.

Discovery of patchy, silver-rich galena at Norton and emphasis on "increased silver exposure" align with strengthening the project’s long-term production profile. Boab’s positioning as "Australia's next major silver producer" highlights silver output and by-product credits as key economic drivers. Re-estimating resources on a combined lead-silver basis could improve reserve grades, extend mine life, and boost returns if silver values are fully integrated into mine planning and pit optimisation.

Geological Model Confirmation and Structural Interpretation Assurance

A significant outcome of Phase IX drilling is validation of the existing geological model across major deposits. Geological model boundaries were intersected with "metre-range accuracy" at all drill sites within the B, Omega, and Norton deposits. This confirms the reliability of structural interpretations, mineralisation geometry, and ore zone continuity assumptions for detailed mine planning and reserve estimation.

Nonetheless, consistent findings that mineralisation intervals exceed previously interpreted shapes suggest opportunities for model refinement and reserve upgrades. The company attributes positive B-Deposit results to a "gentle synform and preservation of the target horizon," indicating geological structures controlling ore geometry are well understood. This enhanced understanding supports confident reserve estimation and pit optimisation. The combination of model validation and broader mineralisation implies reserve estimation may be limited more by data spacing than geological controls, meaning further drilling and sampling could yield meaningful reserve growth by reducing uncertainty.