Silver Mines Boosts Bowdens Silver Project Reserves to 93.5 Million Ounces, Reveals Strong DFS Economics

Record Ore Reserves Elevate Bowdens Silver Endowment to 93.5 Million Ounces

Silver Mines has reported a significant increase in the Bowdens Silver Project's ore reserves, now containing 93.5 million ounces of silver. The updated estimate includes 47.9 million tonnes of ore grading 60.8 grams per tonne silver, with minor zinc and lead credits. This reflects a 46% rise in ore tonnage and a 30% increase in contained silver compared to the January 2025 reserve estimate. The upgrade results from additional drilling, refined geological domains, and enhanced metallurgical insights gained through ongoing exploration and engineering efforts. Silver is projected to contribute roughly 91% of project revenue, up from 85% previously, underscoring Bowdens as a premier primary silver operation.

The expanded reserves reinforce Bowdens’ position among the world’s leading undeveloped silver assets. Resource estimation incorporated 2,248 new assays from 2,265 metres of drilling, boosting geological confidence in deposit size and grade. The updated mineral resource estimate benefits from improved metallurgical knowledge and revised metal price assumptions, strengthening the project's economic viability. Silver’s dominant revenue share simplifies operational planning and market positioning for future production.

Stage 1 Targets 65.4 Million Ounces Over 16-Year Mine Life

The Definitive Feasibility Study outlines a staged development approach starting with Stage 1, which will process 29.9 million tonnes of ore at 68 grams per tonne silver to produce 65.4 million ounces over 16 years. Stage 1 features a low waste-to-ore strip ratio of 1.47:1, supporting efficient mining economics. The mine plan aligns with the capacity of the Stage 1 filtered tailings storage facility engineered to hold 30 million tonnes of filtered tailings. This integrated design reduces permitting risks by clearly defining infrastructure needs.

Stage 2, supported by pre-feasibility engineering and pending approvals, is planned to process an additional 18.3 million tonnes of ore, extending mine life to 26 years. The combined life-of-mine strip ratio is 1.69:1. Stage 2 requires a second filtered tailings facility and carries greater technical uncertainty, while other infrastructure such as processing plant and mining fleet will be shared. This phased approach mitigates risk by completing Stage 1 construction and commissioning before committing to Stage 2.

Capital Investment of A$455 Million Enables Production Start

Stage 1 capital costs are estimated at A$455 million, covering mine development, processing plant construction, tailings infrastructure, site facilities, and related expenditures needed to reach commercial production. Life-of-mine sustaining capital is forecast at A$91 million, funding ongoing equipment replacement, maintenance, and operational infrastructure over 26 years. These capital figures underpin the project’s economic framework and provide clarity for development planning.

All-in sustaining costs are estimated at A$32.91 per ounce (US$23/oz at an exchange rate of 0.70 AUD/USD). During the first five years, AISC is expected to average A$20.47 per ounce (US$14.33/oz), reflecting lower costs during ramp-up. The DFS assumes a conservative silver price of US$35 per ounce, positioning the project competitively within the global silver mining sector and supporting sustainable profitability across various price scenarios.

Strong Financial Returns with A$1.04 Billion Pre-Tax NPV

Economic analysis based on a silver price of US$45 per ounce and A$0.70 exchange rate projects a life-of-mine operating margin of A$2.39 billion and an undiscounted pre-tax operating surplus of A$1.94 billion. The pre-tax net present value at a 5% discount rate is A$1.04 billion, with an internal rate of return of 31.5%. The profitability index of 2.64 indicates substantial value generated per dollar invested. These results highlight the project’s ability to deliver returns well above typical capital hurdles, creating significant shareholder value.

Capital payback is expected within 3 years of production start, with a net present value to pre-production capital ratio of 2.3. Early years forecast pre-tax operating cash flow of approximately A$193 million annually, rising to A$300 million at a US$61 per ounce silver spot price. Average silver production during the first five years is estimated at 4.7 million ounces annually, supporting steady cash flow and shareholder returns.

Development Consent from NSW Government Remains Key Milestone

Securing Development Consent from the New South Wales government is the immediate priority for advancing Bowdens. This approval is essential before further project progression and represents the main regulatory hurdle. While no definitive timeline for consent is provided, Silver Mines remains confident it will be granted in due course. The process includes environmental, social, and economic assessments by state planning authorities and the independent planning commission.

Following consent, the company will pursue federal permitting under the Environmental Protection and Biodiversity Conservation Act 1999 and state mining license approval. Regulatory timelines depend on external factors beyond the company’s control. Silver Mines continues constructive engagement with regulators while advancing technical and engineering studies to support approvals. Managing Director Jo Battershill emphasized the project’s economic benefits to the region, local jobs, and government revenues as positive factors in the approval process.

Advancing Front-End Engineering and Design Post-DFS

With the DFS complete, Silver Mines is progressing into front-end engineering and design (FEED) for Bowdens. This phase will refine technical details, optimize equipment choices, and develop detailed construction plans bridging DFS engineering to construction procurement and execution. FEED involves detailed site assessments, supplier engagement, and engineering refinements across all major systems, validating DFS cost estimates and schedules.

Concurrently, the company is reviewing biodiversity offset strategies to finalize environmental commitments before development begins. This proactive approach addresses permitting requirements and ensures environmental obligations are met. These parallel efforts position Silver Mines to transition smoothly from approvals to detailed construction engineering and early works.

Exploring Production Optimization Opportunities

Silver Mines is investigating potential production optimizations, including ore-sorting technologies and processing plant expansions. Ore sorting could improve mill feed quality, reduce processing of low-grade material, and lower unit costs by increasing effective ore grade. Plant expansion studies will assess the feasibility of increasing throughput beyond Stage 1 design, potentially unlocking additional resource tonnage.

These initiatives demonstrate the company’s commitment to value enhancement as geotechnical understanding, commodity prices, and technology evolve. The modular approach allows capital commitment to Stage 1 while maintaining flexibility to implement improvements post-commissioning, reflecting advanced project management and technical rigor.

Project Supports Regional Employment and Government Revenues

Bowdens is expected to generate significant regional economic benefits in New South Wales. The project anticipates employing over 200 personnel at steady state, offering long-term local job opportunities amid economic shifts from Australia’s coal industry decarbonization. With a planned operational life exceeding 25 years, Bowdens will provide stable employment and economic activity.

Additionally, the project will contribute substantial tax and royalty payments to state and local governments. Silver Mines has also entered a voluntary planning agreement with local council to support community benefits and infrastructure. These economic contributions align project development with regional interests and may facilitate regulatory approvals.

Silver’s Revenue Dominance Clarifies Project Economics

Bowdens is structured as a primary silver mine, with silver accounting for approximately 91% of mining revenue, up from 85% in the prior estimate. Zinc and lead, at grades of 0.36% and 0.26% respectively, provide byproduct credits that partially offset costs. The silver-focused revenue stream simplifies operational decisions compared to polymetallic projects and concentrates economic sensitivity on silver prices.

The company notes that 95% of revenue in the first five years derives from NSW critical minerals, with silver comprising 94% of that revenue. This focus limits exposure to base metal price volatility and reinforces Bowdens as a premier silver development.

DFS Shows Material Improvements Over Prior Optimization Study

The Definitive Feasibility Study marks significant progress from the December 2024 Optimization Study. Contained silver reserves increased from 71.7 million ounces in January 2025 to 93.5 million ounces in 2026, reflecting additional drilling and refined mining and processing assumptions. Although detailed comparisons are not disclosed, the DFS advances technical and economic confidence.

This progression exemplifies standard project development practices, with each study incorporating more detailed work and assumptions refinement. Silver Mines’ updates demonstrate disciplined management and provide a strong foundation for regulatory approvals and development engineering phases.