Can Great Boulder Turn Ironbark’s 100,000 oz Resource into Gold Mine Gold?

Overview of the Ironbark Scoping Study

Great Boulder Resources (ASX – GBR) has unveiled the results of an independent scoping study on its Ironbark deposit, a key component of the Side Well Gold Project near Meekatharra in Western Australia. The study, conducted by Entech Pty Ltd, outlines a robust mining opportunity supported by a Mineral Resource Estimate (MRE) of 100,000 ounces at a high grade of 3.3 grams per tonne gold (g/t Au) within the broader Side Well resource of 668,000 ounces at 2.8 g/t Au.

The Ironbark deposit is characterised by shallow, high-grade gold mineralisation with simple geometry, making it amenable to open pit mining. The scoping study proposes a two-stage open pit design with a 31-month mine life, targeting approximately 79,000 ounces of gold production over this period.

Financial Highlights and Project Economics

Financial modelling based on a gold price of AUD 4,000 per ounce delivers a compelling pre-tax net present value (NPV8) of approximately AUD 137 million and an internal rate of return (IRR) of 152%. The study assumes capital expenditure of AUD 3.1 million for surface infrastructure establishment and operating costs benchmarked against comparable Western Australian open pit operations.

Processing is planned via toll milling at one of several nearby facilities, including Westgold’s Bluebird mill, Meeka Metals’ Andy Well plant, or Monument Mining’s Burnakura mill, with commercial agreements yet to be finalised. The company has also signed a Memorandum of Understanding with Monument Mining, potentially facilitating access to the Burnakura plant.

Technical and Operational Considerations

The mine plan incorporates detailed pit optimisation and scheduling, with mining operations designed around a fleet of 120-tonne excavators and 90-tonne haul trucks. The study includes allowances for mining dilution and recovery, metallurgical recoveries of 95% for oxide and transitional material and 92% for fresh rock, based on preliminary test work.

Environmental baseline studies and hydrogeological investigations are underway, supporting the company’s plan to lodge mining approval applications following the anticipated grant of the mining lease. Negotiations with the Yugunga-Nya Native Title Aboriginal Corporation are progressing, with ratification expected by November 2025.

Risks and Next Steps

While the scoping study presents a positive outlook, it remains a preliminary assessment with an accuracy of +/-30%. Notably, recent high-grade drilling results south of Ironbark have not yet been incorporated into the resource or study. No Ore Reserves have been declared, and the production target includes 11% Inferred Resources, which carry inherent geological uncertainty.

Key risks include securing the necessary funding, estimated capital requirements are modest but timing and terms remain uncertain, as well as finalising processing agreements and obtaining regulatory approvals. Great Boulder plans further drilling to upgrade resource confidence, comprehensive metallurgical testing, and submission of mining lease applications in the coming months.

Overall, the Ironbark scoping study reinforces Great Boulder’s strategy to develop a high-grade, near-term gold mining operation within the Side Well Project, setting the stage for more definitive studies and potential project advancement.