Greater Duchess Project Targets 165,000t CuEq with A$472M NPV and 13-Month Payback

Project Overview and Financial Highlights

Carnaby Resources Limited (ASX:CNB) has announced the results of its Pre-Feasibility Study (PFS) and maiden Ore Reserve for the Greater Duchess Copper Gold Project, located in the Mt Isa region of Queensland. The study outlines a 12-year mine life with a production target of 9.3 million tonnes at an average grade of 1.9% copper equivalent, yielding approximately 165,000 tonnes of copper equivalent metal.

Financially, the project demonstrates robust metrics with a pre-tax net present value (NPV) at a 7% discount rate of A$472 million and an internal rate of return (IRR) of 281%. The pre-production capital expenditure is modest at A$11 million, supporting a rapid payback period of just 13 months. Under spot commodity prices, these figures improve further, highlighting the project's resilience to market conditions.

Mining and Operational Plan

The mining strategy involves an initial six years of open pit mining transitioning to nine years of underground operations. The maiden Ore Reserve totals 8.4 million tonnes at 1.9% copper equivalent, split evenly between open pit and underground sources. Open pit mining will focus on six deposits including Trek 1, Trek 2, Inheritance, Mount Hope Central, Lady Fanny, and Burke & Wills, while underground mining will target Mount Hope Central and Nil Desperandum deposits.

Ore will be crushed onsite and transported by road haulage to Mount Isa for toll processing under binding agreements with Glencore International AG. This arrangement leverages existing world-class infrastructure, reducing capital intensity and operational risk. Carnaby retains the option to develop its own concentrator with appropriate notice to Glencore, providing strategic flexibility.

Environmental, Social, and Governance (ESG) Considerations

Carnaby has integrated ESG principles into project planning, recognising their importance for sustainable development and social licence to operate. The project area is subject to ongoing environmental assessments, with preliminary studies indicating manageable risks related to acid and metalliferous drainage. Engagement with Traditional Owners, including the Kalkadoon and Yulluna Peoples, is underway with heritage and land access agreements in place or being negotiated.

Permitting is progressing, with some mining leases already granted and environmental authorities established. The company is preparing minor and major amendments to support full project development, aiming for timely approvals aligned with the production schedule.

Funding and Next Steps

With a strong cash position of A$16 million as of December 2025 and a tight capital structure, Carnaby anticipates a funding requirement of approximately A$25 million to cover capital and operating costs through to economic production. The company expects to meet this through a combination of debt and equity, though the exact structure remains to be determined.

The feasibility study is well advanced and targeted for completion by mid-2026, with a final investment decision (FID) expected by the end of June 2026. First production is targeted for the second half of 2026, marking a significant milestone for Carnaby and its shareholders.

Technical and Market Context

The PFS incorporates extensive technical work including detailed geological modelling, mine design, metallurgical testwork, and economic evaluation. Metallurgical recoveries for copper exceed 90% for fresh sulphide ores, supporting the project's economic viability. Sensitivity analysis confirms the project's value is most influenced by copper prices and foreign exchange rates, with operating costs and gold prices also significant factors.

Market-wise, the project benefits from proximity to established processing facilities and infrastructure, reducing logistical complexity. The binding tolling and offtake agreements with Glencore provide a secure pathway to market, mitigating commodity price and sales risks.