Great Boulder Unveils $137M Ironbark NPV Amid Busy Side Well Drilling Campaign

Exploration Momentum at Side Well

Great Boulder Resources Ltd (ASX, GBR) has delivered a notably active June quarter, marked by over 14,700 metres of drilling at its flagship Side Well Gold Project near Meekatharra, Western Australia. This drilling forms part of an ongoing resource definition and discovery program that has seen the company complete 536 holes totalling 55,564 metres in the past year, underscoring a sustained commitment to expanding its gold resource base.

Particularly encouraging are the results from Side Well South, where recent reverse circulation (RC) drilling has confirmed significant gold mineralisation over more than 200 metres of strike, with mineralisation remaining open along strike and at depth. High-grade intersections such as 8 metres at 9.07 g/t gold and 8 metres at 8.57 g/t gold highlight the prospectivity of this area. The company plans to continue drilling to further define these zones and incorporate them into an updated mineral resource estimate.

Ironbark Scoping Study Highlights Robust Economics

In parallel with exploration, Great Boulder has advanced development studies at the Ironbark target within the Side Well Project. A recently completed scoping study outlines a potential open-pit operation processing 500,000 tonnes per annum over a 31-month mine life. The study is based on a 1.26 million tonne resource grading 2.0 grams per tonne gold, targeting approximately 79,000 ounces of gold production.

Financially, the study is compelling, delivering a pre-tax net present value (NPV) at an 8% discount rate of A$137 million and an internal rate of return (IRR) of 152%, assuming a gold price of A$4,000 per ounce. Sensitivity analysis indicates the NPV could range from A$100 million to A$165 million with gold prices between A$4,500 and A$5,500 per ounce. These metrics suggest Ironbark could be a highly profitable operation, pending further technical and regulatory approvals.

Metallurgical Advances and Project Approvals

Metallurgical test work at the Mulga Bill deposit, part of the Side Well Project, continues to impress. Independent testing has demonstrated excellent gold recoveries exceeding 92% at low cyanide concentrations, with rapid leach times and significant gravity recoverable gold. These results bode well for processing efficiency and environmental considerations, potentially reducing reagent consumption and operational costs.

Great Boulder has also appointed an Approvals Manager to coordinate government applications for mining at Ironbark, signaling progress towards securing the necessary permits to advance development. Concurrent technical studies, including hydrogeology, waste characterisation, and geotechnical analysis, are underway to support these approvals.

Corporate and Portfolio Developments

On the corporate front, Great Boulder successfully completed a two-tranche capital raising, securing A$12.5 million at 6.1 cents per share, anchored by a North American mining fund. This capital injection strengthens the company’s balance sheet, which stood at A$12.48 million in cash with no debt at quarter’s end.

Meanwhile, the divestment of the Whiteheads Project to Hastings Technology Metals Ltd is nearing completion, with due diligence and finalisation expected by August 2025. This sale allows Great Boulder to focus resources on its core gold projects while realising value from non-core assets.

Looking Ahead

Great Boulder’s exploration and development activities are poised to continue at a brisk pace. Upcoming drilling at Side Well South and Ironbark aims to expand and upgrade resources, while metallurgical testing and permitting efforts advance. The company’s strategic capital raise and asset rationalisation position it well to progress towards production in the medium term.