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

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

Boab Metals Limited is an Australian exploration and development firm 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 significant silver producer. Fully funded and under construction, Boab is conducting targeted geological and exploration activities to unlock further value from its resource base.

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

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 main components: resource-to-reserve conversion drilling aimed at upgrading parts of the existing Mineral Resource for detailed mine planning and scheduling; silver-focused resource expansion drilling targeting extensions to known mineralisation, especially silver intercepts previously excluded due to lead-only below cut-off grades; and exploration drilling across the broader Sorby Hills tenure based on geological interpretations and historical data.

Boab clarified that reserve conversion drilling is not a prerequisite for accessing the project finance debt facility, highlighting the program’s discretionary and value-enhancing nature. The total Phase IX program plans approximately 5,000 metres of drilling, with 28 sonic and diamond core holes completed to date, totaling about 3,000 metres. All drilling at the B-Deposit, Omega-Deposit, and Norton-Deposit—the primary resource areas in the FEED Study—has been completed, with remaining efforts focused on Beta Deposit, Keep Target, and a deep hole at the Manbarrum Project.

B-Deposit Drilling Outcomes and Pit Expansion Prospects

At the B-Deposit, seven drill holes targeted the eastern down-dip perimeter and up-dip areas where positive results could enhance reserve estimates and mine planning. The drilling intersected the targeted mineralised horizons with metre-range accuracy, validating the current geological model. Notably, mineralisation widths exceeded those predicted by nearby intercepts, suggesting potential for increased ore tonnage.

Drill hole SHSD_205 is expected to 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 may increase ore zone thickness at depth, possibly enlarging the pit shell and ore volume. These positive outcomes are attributed to a gentle synform structure and preservation of the target horizon, indicating the B-Deposit could possess greater mineral endowment than currently reflected in the FEED Study, with implications for reserve growth and mine-life extension.

Omega-Deposit Mineralisation Wider Than Geological Models

At Omega-Deposit, 18 drill holes mainly along the eastern down-dip perimeter tested mineralisation near the northern edge but outside the current FEED Study pit shell. Geological boundaries were intersected with metre-range accuracy, confirming structural interpretations. However, mineralisation widths frequently exceeded previous model shapes, signaling promising resource and reserve growth potential.

Notable mineralisation was observed visually in drill holes SHSD_195 (Omega South) and SHSD_214 (north). The economic impact of grade and mineralisation thickness at depth awaits laboratory assays and optimisation. Over 860 samples from reserve conversion drilling have been submitted for analysis, with results pending across all three main deposits. The broader-than-modelled mineralisation at Omega suggests opportunities for further ore reserve conversion and potential mine-life extension once assay data is available.

Norton Deposit High-Grade Galena Extensions and Silver Upside

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

Results from SHSD_216 are expected to enhance the cluster of high-grade intercepts north of the current pit, affirming the extent and grade of this zone despite separation by a low-grade breccia zone. This discovery supports expansion of the high-grade zone and increased silver production potential. The hole also confirmed patchy silver-dominant galena mineralisation, aligning with Boab’s strategy to target silver-rich extensions previously excluded due to lead-only cut-off grades. These findings underpin the company’s goal of boosting silver exposure and long-term production value.

Mineralisation Extending Beyond FEED Study Pit Designs

A key outcome of Phase IX drilling is the consistent observation that mineralisation extends beyond pit designs in the FEED Study across multiple deposits. Several drill holes encountered broader mineralised intervals than currently modelled, indicating potential resource and reserve growth. This pattern spans the B-Deposit, Omega-Deposit, and Norton-Deposit, the three main resource areas supporting the mine plan.

This consistency suggests the current geological model may be conservative in some areas, possibly due to historical data 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, ore 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 B-Deposit, Omega-Deposit, and Norton-Deposit for laboratory analysis. Assay results have not yet been released; the Managing Director noted "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 lab data.

Assay result timing will be crucial for investors tracking project progress. While visual observations are encouraging, final reserve and resource upgrades depend on laboratory grade analysis and reserve modelling. Boab intends to release results progressively, not waiting for all analyses to complete before market updates. Management’s commentary that these observations provide "growing confidence that the program can deliver additional Ore Reserves" signals positive expectations, with final quantification pending assay data and reserve estimation.

Strategic Value Creation and Financing Context

The Phase IX drilling program is strategically designed to capture upside at Sorby Hills while fully funded and under construction. Boab’s Managing Director stated, "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 view that reserve growth and mine-life extension during construction can materially enhance project returns and shareholder value.

The company emphasized that reserve conversion drilling is not required to draw on the project finance debt facility, indicating this program is discretionary and value-additive rather than mandatory for development. This financial flexibility reflects confidence in project economics without additional reserve growth. However, investing in Phase IX drilling during construction demonstrates management’s conviction that meaningful reserve upgrades are achievable and economically justified. Potential increases in ore reserves, mine life beyond the FEED Study timeline, and silver production exposure position Boab to unlock additional 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, particularly silver intercepts previously excluded due to lead-only cut-off grades. This approach acknowledges silver’s premium value and that current resource estimates may understate silver endowment. The company noted this work "may support a re-estimation of the Mineral Resource on a combined lead-silver basis and potential mine-life extensions," implying current estimates are lead-focused and may exclude economically valuable silver mineralisation.

Identification of patchy silver-dominant galena at Norton and emphasis on "increased silver exposure" and "strengthening the long-term production profile" highlight silver production as a key objective. Positioning as "Australia’s next major silver producer" underscores silver output and by-product credits as vital to project economics. Resource re-estimation on a combined lead-silver basis could improve reserve grades, extend mine life, and enhance returns if silver values are fully integrated into mine planning and pit optimisation.

Geological Model Validation and Structural Confidence

A critical Phase IX outcome is validation of the existing geological model across all main deposits. Geological model boundaries were intersected with "metre-range accuracy" at all drill sites in B-Deposit, Omega-Deposit, and Norton-Deposit, confirming structural interpretations, mineralisation geometry, and ore zone continuity assumptions used for mine planning and reserve estimation.

However, mineralisation intervals often exceeded shapes interpreted from nearby intercepts, indicating opportunities for model refinement and reserve upgrades. Positive results at B-Deposit may reflect a "gentle synform and preservation of the target horizon," validating geological controls on ore body geometry. This improved understanding supports confident reserve estimation and pit optimisation. The combination of model validation and broader-than-modelled mineralisation suggests reserve estimation is more constrained by data spacing than geological factors, implying further drilling and sampling can drive meaningful reserve growth by reducing uncertainty.