Alma Metals Commences Major Drilling to Expand Briggs Copper Resource

Drilling Campaign Targets Resource Upgrade and Growth

Alma Metals (ASX:ALM) has kicked off a substantial drilling program at its Briggs Copper Project in Central Queensland, a move designed to bolster the Mineral Resource Estimate (MRE) and underpin advancing pre-feasibility studies (PFS). The current resource, which holds 2 million tonnes of contained copper at a 0.15% cut-off, ranks Briggs among the top tier of Australia's undeveloped copper deposits. This campaign aims to upgrade the bulk of inferred resources to the more certain indicated category, test the depth extensions where promising high-grade copper has been encountered, and explore new targets beyond the existing resource boundary.

The program's scale and ambition reflect Alma’s intent to transition Briggs from exploration to development, with the drilling set to run for 12 to 15 months. Initial efforts focus on infill drilling to support early mining phases, with 41 holes planned to convert inferred resources to indicated by the end of 2026. A second phase in early 2027 will aim to upgrade the remaining inferred resource, setting the stage for an updated MRE to feed into engineering and mine scheduling components of the PFS. This approach builds on the project's already robust foundation, highlighted in earlier 2Mt copper resource and PFS plans.

Expanded Team and Accelerated Drilling Operations

To support this ambitious program, Alma has expanded its project team, appointing specialists in geology, logistics, and safety management. This staffing boost enables the company to deploy multiple rigs operating day and night shifts, accelerating the drilling pace. Currently, one diamond drill rig operates on day shifts, with a second rig scheduled to join early next quarter. The program also includes four exploration holes targeting copper anomalies outside the current MRE, potentially expanding the resource within the mining footprint.

Managing Director Frazer Tabeart emphasised the significance of this phase, noting the compelling upside potential given the system remains open at depth and to the west, with strong grades from the deepest holes. The drilling strategy aligns closely with ongoing metallurgical, environmental, and engineering workstreams, all feeding into the PFS. This integrated approach is intended to optimise copper, molybdenum, silver, and gold recoveries, as well as provide critical geotechnical data for open pit design.

Metallurgical and Environmental Workstreams Complement Drilling

Metallurgical test work continues in parallel, aiming to refine recovery processes and update the mineral processing flowsheet. Previous studies have demonstrated potential copper recoveries of around 95% into high-grade concentrates, with valuable by-products such as molybdenum and silver also present. Environmental baseline surveys are underway, with consultants engaged to characterise waste and tailings chemistry, crucial for the PFS environmental assessments.

Briggs benefits from its strategic location near Gladstone Port and existing infrastructure, including power, rail, gas pipelines, and major highways, all of which enhance its economic viability. Alma currently holds a 51% interest in the project under a joint venture with Canterbury Resources and is progressing toward increasing its stake to 70% by completing the earn-in phase.

This drilling campaign follows a series of encouraging results from late 2025 and early 2026, including record copper intersections and high-grade zones that have bolstered confidence in resource expansion and development plans. The company's recent record copper intersections and capital raise underpin this accelerated push into prefeasibility studies, reflecting strong market fundamentals for copper driven by supply deficits and demand growth.