Aeris Resources Quadruples Tritton Ore Reserves to 10 Million Tonnes

Aeris Resources (ASX: AIS) has lifted the Tritton operations ore reserve estimate (ORE) more than fourfold to 10 million tonnes, containing approximately 180,000t of copper, as it builds a long-life, multi-mine hub around its existing processing infrastructure.

The Tritton mineral resource estimate (MRE) increased 70% to 33Mt at 1.7% copper, containing about 540,000t of copper compared with 310,000t previously.

Growth came from the integration of the Mallee Bull and Wirlong deposits, maiden underground reserves at Constellation and Mallee Bull, and successful exploration and resource definition drilling at Avoca Tank and Budgerygar.

The expanded inventory will inform an updated life of mine plan and production target that Aeris expects to release in the first half of FY27.

Nine of the 10 known deposits within the Tritton tenement package remain open down dip, supporting Aeris' plan to continue resource extension work around established underground infrastructure.

Underground Drilling Tripled

Mallee Bull and Wirlong—added through the recent acquisition of Peel Mining—contributed a combined 11Mt and about 200,000t of copper to the MRE, including about 160,000t classified in the Indicated category.

Aeris tripled underground diamond drilling during FY26, with exploration and resource definition programs at Avoca Tank and Budgerygar adding more than 2Mt to the resource base.

Avoca Tank contributed a net increase of 0.9Mt and 14,000t of copper, while Budgerygar added 1.3Mt and 18,000t after drilling refined the scale and continuity of its mineralisation.

The MRE is inclusive of the ORE and is not an additional inventory that can be added to the reserve base.

New Mines Lift Reserve

Constellation now accounts for a 5.3Mt ORE at 1.5% copper containing about 80,000t, comprising a maiden underground component of 3.8Mt at 1.6% copper containing about 62,000t and 1.46Mt of oxide, supergene, and sulphide open pit reserves containing about 18,000t.

The maiden Mallee Bull underground ORE comprises 2.7Mt at 2.4% copper containing about 66,000t, making it another substantial potential ore source for the Tritton processing plant.

Budgerygar's ORE reached 0.92Mt at 1.4% copper containing about 13,000t after additional Indicated mineral resources were converted through mine design and evaluation.

The Constellation and Mallee Bull reserves were prepared to pre-feasibility study (PFS) standard, with the PFS work incorporating mine design, production scheduling, geotechnical, metallurgical, infrastructure, and economic evaluations.

Longer-Term Pipeline

Aeris plans about 85,000m of underground drilling across Tritton in FY27, continuing the strategy that delivered material growth at Avoca Tank and Budgerygar during FY26.

At Constellation, resource definition drilling will target the remaining 0.5Mt of Inferred mineral resources within the open pit for potential conversion to Indicated status before mining, alongside metallurgical test work and plant trials on oxide material.

At Mallee Bull, Aeris will continue mine plan and schedule optimisation, feasibility studies including ore transport options, exploration decline planning, and permitting work, while further reserve growth remains dependent on exploration success, technical studies, approvals, and economic conditions.

“With more than 10 million tonnes now in Ore Reserve, equivalent to more than five years of mill feed at the current processing plant capacity, we have established a strong foundation for a long-life, multi-mine copper operation centred on our existing Tritton processing infrastructure,” executive chair André Labuschagne said.

“The expanded mineral resource and ore reserve inventory at Tritton will underpin the development of an updated Life of Mine plan showing the long-term potential of the operation.”