Meridian Smelter Tests Deliver High Quality Blister Copper from Cabacal Copper Concentrates

Meridian Mining PLC (MNO) announced the results of laboratory-scale smelting and converting tests on copper concentrates from its Cabaçal project. Conducted at Kingston Process Metallurgy in Ontario, the tests produced blister copper containing 98.9% copper, 95.2 g/t gold, and 387.6 g/t silver, alongside extremely low impurity levels. These impurities included Fe at 0.02%, S at 0.95%, Pb at 0.002%, Zn at 0.002%, and As at 0.009%, a composition that outperforms typical industry anode copper.

During the smelting stage, copper recovery reached 95%, with slag copper content limited to 0.37%. The process upgraded matte from approximately 26.3% Cu to 62% Cu, which was then converted to high-sulphur blister copper. Management stated that the results position Cabaçal’s concentrate as a premium blending feedstock capable of upgrading lower-quality third-party concentrates, a value proposition that aligns with current low treatment charges and strong demand for clean copper concentrates.

The company plans to use this data to engage off-takers and advance project finance, with samples being made available to counterparties. The Definitive Feasibility Study (DFS) remains on track for completion in Q4 2026. The release also referenced the March 2025 Preliminary Feasibility Study (PFS) economics, which cited an after-tax NPV5 of $984M, an IRR of 61.2%, pre-production capex of $248M, and an AISC of $742/oz AuEq. These figures are based on reserves of 41.7Mt at 0.63 g/t Au, 0.44% Cu, and 1.64 g/t Ag.

Meridian Mining PLC (MNO) confirmed that its Cabaçal copper concentrate is marketable as a premium product, featuring strong precious-metal credits and an impurity profile well below typical smelter standards. This validation supports off-take negotiations and project finance efforts, though it does not introduce unexpected new information. The smelter test serves as a follow-up to earlier metallurgical work, as the Preliminary Feasibility Study (PFS) already assumed a 92.3% copper recovery and saleable concentrate. While the blister copper purity and impurity data are new, they represent an incremental validation rather than a fundamental change in project economics.

The news references the same PFS metrics cited in previous releases, with no updates to reserves, resources, capital expenditure, or project timelines. The Definitive Feasibility Study (DFS) remains in progress. In the context of the company’s recent progression—including securing a London Stock Exchange listing, closing $57.5 million in financing, and advancing permitting—this operational update is viewed as positive but routine. It does not materially alter the investment thesis or the stock’s risk profile.

The market’s likely response is expected to be mildly positive, although the share price had already declined from May highs of $2.13 to $1.37, reflecting broader risk-off sentiment or sector rotation. This type of news is unlikely to reverse that trend on its own.

Meridian Mining PLC (MNO) is a pre-revenue junior explorer and developer focused on the Cabaçal gold-copper-silver Volcanogenic Massive Sulphide (VMS) project in Mato Grosso, Brazil. The company is also advancing the nearby Santa Helena Central deposit and exploring a 50 km belt-scale corridor.

The flagship Cabaçal project hosts a Pre-Feasibility Study (PFS)-stage open-pit mine with Proven and Probable reserves of 41.7 million tonnes at 0.63 g/t Au, 0.44% Cu, and 1.64 g/t Ag, based on a cut-off of 0.25 g/t AuEq. An update in January 2026 reported Measured and Indicated resources totaling 70.1 million tonnes at 0.56 g/t Au, 0.33% Cu, and 1.31 g/t Ag. The PFS, completed in March 2025, outlined robust economics including a post-tax NPV5 of $984 million, an internal rate of return (IRR) of 61.2%, capital expenditure of $248 million, an all-in sustaining cost (AISC) of $742 per ounce AuEq, and a 10.6-year mine life producing 141,000 ounces of AuEq annually.

A Definitive Feasibility Study (DFS) is currently underway, reaching 50% completion as of May 2026, with reporting expected in the fourth quarter of 2026. Permitting is advancing, with a Preliminary Licence granted in October 2025 and an Installation Licence submitted in May 2026. An Operating Licence is planned for the second half of 2028.

Secondary assets include the Santa Helena Central deposit, which received a maiden Measured and Indicated resource of 5.3 million tonnes at 0.56 g/t Au, 0.43% Cu, 15.45 g/t Ag, 1.86% Zn, and 0.43% Pb in January 2026, with further exploration upside identified. Regional targets include the Alamo, Cigarra, and Espigão (IOCG) projects, as well as the Jauru and Araputanga greenstone belts.