ASX-listed Sandfire Resources has reported an updated measured, indicated and inferred mineral resource estimate (MRE) for the MATSA mining operations, in Spain, totalling 147.2-million tonnes, containing an estimated 2.1-million tonnes of copper, 4.4-million tonnes of zinc, 1.5-million tonnes of lead and 187.6-million ounces of silver.

The updated MRE, reported as at December 31, 2021, represents Sandfire’s first MRE for MATSA since it assumed ownership of the project in February, with the company employing rigorous estimation and reporting methodologies including constraining the mineral resource to exclude sections of the orebodies unlikely to be accessible from planned workings.

The strong outcome confirms MATSA’s geological potential as assessed by Sandfire during its due diligence process for the project acquisition, delivering a robust and high-quality MRE that will provide a strong platform for future life-of-mine (LoM) planning, the company says.

Importantly, Sandfire highlights that about 74% of the updated MRE is classified in the higher confidence measured and indicated (M&I) resource categories.

An updated ore reserve estimate for the MATSA mining complex is scheduled for delivery in the September quarter.

When compared with the previous MRE reported as at December 31, 2019, the updated December 2021 MRE delivers a 21% increase in contained tonnes, an 11% increase in contained copper and a 10% increase in contained zinc.

This more than replaces mining depletion over the intervening two-year period.

The updated MRE also includes initial inferred mineral resources for the satellite Concepción, Poderosa and Castillo-Buitrón deposits totalling 19.8-million tonnes. All three deposits are located close to the existing 4.7-million-ton-a-year processing plant.

Mineralisation within the updated MRE comprises two key material types – polymetallic and cupriferous/stockwork.

These material types are processed through the 4.7-million-ton-a-year Aguas Teñidas processing plant using separate processing streams.

Mineralisation at all three mines is dominated by massive sulphides, with the dominant sulphide mineral being pyrite with lesser amounts of sphalerite, chalcopyrite and galena.

“The completion of our first-ever MRE for MATSA is a tremendous achievement which confirms the world-class nature of the asset, validates our due diligence assessment prior to the acquisition, and sets a strong long-term platform for growth.

“Importantly, this mineral resource has been completed to a very high standard, employing rigorous industry best practice estimation techniques and robust net smelter royalty, or NSR, methodology,” acclaims MD and CEO Karl Simich.

“The key takeaway for investors is therefore that this is a high-quality resource with 109-million tonnes in the high-confidence M&I categories, which provides a strong platform for LoM optimisation and planning, with an updated ore reserve estimate scheduled for completion in the September quarter,” he adds.

 “This mineral resource represents an outstanding first step for Sandfire at MATSA and we have every confidence that this exceptional asset will continue to grow and develop in the months and years ahead, forming the backbone of our ambition to become a sector-leading international base metals producer,” Simich acclaims.