Marimaca Copper drills 70 m of 1% Cu at Pampa Medina

Mr. Hayden Locke reports HIGH-GRADE SEDIMENT HOSTED MINERALIZATION EXTENDED AT PAMPA MEDINA 300M WESTERN STEP-OUT SMRD-16 INTERSECTS 10M OF 4.2% CU WITHIN 70M OF 1.0% CU Marimaca Copper Corp. has conducted further drilling at the Pampa Medina deposit, extending the high-grade sediment-hosted manto-system 300 metres to the west from previous drilling. Pampa Medina is located at low altitude approximately 28 kilometres east of the company's Marimaca oxide deposit (MOD) in a flat pampa valley within the Atacama Desert. The company is executing a 10,000-metre extensional drilling program with three rigs currently on site. Highlights Hole SMRD-16 extends the high-grade manto-system a farther 300 m to the west, with varying depths of the oxide to sulphide transition: Further validation of the Pampa Medina exploration model: a unique stratiform, sediment hosted, copper system with extensive high-grade sequences. Interbedded sandstone, shale and conglomerate units continue to deliver the highest-grade zones (greater than 1 per cent Cu (copper)) across broad thicknesses. The favourable mineralized stratigraphic sequence is now defined by drilling across a 1.2-kilometre-by-1.2-kilometre area at the Pampa Medina deposit and remains open -- extensional drilling will focus on the north and the west. Highlights from SMRD-16 (true widths estimated to be 95 per cent of reported intersection): 70 metres of 1.0 per cent from 434 m including: 10 m of 4.2 per cent Cu from 438 m down hole within 30 m of 2.1 per cent Cu from 434 m; Oxide and secondary sulphide. 116 m of 0.61 per cent Cu from 516 m including: Eight m of 1.8 per cent Cu from 528 m (sulphide); 10 m of 1.2 per cent Cu from 568 m (sulphide); 20 m of 1.1 per cent Cu from 612 m (sulphide). 50 m of 0.53 per cent Cu from 744 m including: 10 m of 1.1 per cent Cu from 782 m (sulphide). Hole SMRD-15 demonstrates uplifting of the eastern extension, with a broad zone of near-surface oxide mineralization intersected at 122 m down hole in hosted by remnants of sediments just above the contact with basement rocks: SMRD-15 intersected 42 m of 0.51 per cent Cu from 158 m. SMRD-16 extends the high-grade mineralized manto 300 m west along section from previously reported holes. Hole SMRD-13 (300 m west of SMRD-15): Six m of 12.0 per cent Cu from 594 m down hole within 26 m of 4.1 per cent Cu from 580 m and a broader 100 m of 1.3 per cent Cu from 580 m. Hole SMD-02 (600 m east of SMRD-16 on section) (previously reported): 40 m of 2.1 per cent Cu from 282 m down hole within 132 m of 1.0 per cent Cu from 278 m. Hole SMRD-12 (300 m east of SMRD-16 on section) (previously reported): 56 m of 1.4 per cent Cu from 566 m down hole. Similar to the MOD, Pampa Medina's location is expected to drive significant infrastructure and permitting benefits: Proximity to other mines and associated infrastructure: 28 kilometres from the MOD, 64km from Sierra Gorda (South32/KGHM), 40 km from Mantos Blancos (Capstone Copper), 77 km from Spence (BHP) and 54 km from Antucoya (Antofagasta Minerals); Low altitude, flat pampa type surface provides sufficient space for future facilities and infrastructure; Proximity to existing powerlines, water pipelines, major ports and regional populations; No private land ownership, limited human impact (no nearby local or indigenous population), extremely arid location indicates low permitting risks (comparable or superior to the MOD) associated with potential development. Sergio Rivera, vice-president of exploration of Marimaca Copper, commented: "SMRD-16 is a farther 300 m step out to the west of the previously announced SMRD-12 and has intersected a similar broad zone of high-grade copper mineralization, including 70 m at 1.0 per cent and a number of discrete very high-grade zones. "The area of interest currently confirmed by drill intersections extends over 1.2 km east-west by 1.2 km north-south, with an average true thickness of between 50 m to 100 m. We currently have no observable reasons to indicate that mineralization would not be continuous while the sedimentary unit exists and, as a result, we see enormous potential to both the north and west of the current drilling. "To the east, the block was uplifted significantly, which caused a thinning of the mineralization. Despite this, we intersected a broad zone of oxide copper mineralization at above economic cut-off grades for Pampa Medina and we, therefore, continue to see strong potential for oxide resource growth in all directions. "Our strategy remains to step out significantly to try to define the limits of what is a very large system, but we will now also turn our attention to planning an infill campaign in the broader Pampa Medina project area with the objective of delineating updated resources for the project." Hayden Locke, president and chief executive officer of Marimaca Copper, commented: "The depth of these new intersections continue to indicate that it will be an underground opportunity, once the Pampa Medina oxide open pit has been considered. Our early analysis indicates an economic cut-off grade requirement of between 0.5 per cent and 0.8 per cent, depending on copper price. With that in mind, we are targeting mineralized intersections with true widths exceeding 20 m at an average copper grade of 1.0 per cent or more. The last four drill holes have delivered widths and grades that materially surpass this requirement and, as a result, we see enormous potential for a large-scale, highly economic, underground copper mining opportunity. "Sergio Rivera and our exploration team continue to deliver outstanding value with the extension of the thick, high-grade manto mineralization to the west. The continued exploration success at Pampa Medina reinforces our goal at Marimaca: to become a significant copper producer with the unique, low-cost, advanced-stage asset in the MOD and transformational district scale upside anchored by Pampa Medina and Madrugador. "With the upcoming release of the MOD DFS, our strategy remains multipronged: 1) deliver a near-term, low-cost 50,000 tpa copper cathode mine in a Tier 1 jurisdiction; 2) advance the Pampa Medina and Madrugador oxide projects to grow our cathode production and extend mine life; and 3) continue to define the district-scale exploration potential of our large land package." Overview of Pampa Medina Pampa Medina is a stratiform or manto-style copper deposit dominantly hosted in Jurassic-Triassic sedimentary units (sandstones, conglomerates, tuffs and black shales) overlain by andesitic volcanics and underlain by an Upper Paleozoic complex of metamorphosed sediments, volcanics and intrusions. Its intruded by a dyke swarm and affected by postmineral normal faulting. Copper was originally identified in near-surface oxide mineralization dominated by atacamite, chrysocolla, and both secondary and primary chalcocite, and has now been identified in high-grade zones of chalcopyrite and bornite which extend laterally down-dip beyond the oxide-primary transition. Following Marimaca's consolidation of the project area and surrounding land packages in 2024, the company reinterpreted all available geological information (for the first time as one) and developed an updated geological model for Pampa Medina, which identified the lower sedimentary units of interbedded sandstones, shales and conglomerates as the productive horizons for future drill targeting. Oxide copper mineralization was logged in historical drilling in near-surface, uplifted blocks, with the model of continuity in the intact lithological sequence in deeper blocks for primary mineralization to be tested by Marimaca's 2025 drilling campaign. SMRD-16 materially extends the high-grade manto to the west, increasing the defined mineralized stratigraphy across a 1.2 km by 1.2 km area. Weakly mineralized sandstones were intercepted from 116 m, with the main high-grade mixed-sulphide, sediment hosted mineralization starting at 438 m down hole. Hole SMRD-15 was planned to confirm the uplifted basement in the eastern direction of the Pampa Medina main target. Oxide mineralization was intercepted at 122 m, extending to 204 m depth. Exploration focus will remain on the western and northern regions of the Pampa Medina main target, which both remain open. Sampling and assay protocols True widths are estimated as 95 per cent of reported intervals, based on down-hole bedding and structural measurements. DDH holes were sampled on a two m continuous basis, halved by a conventional core splitter on site with one half sent to the Andes Analytical Assay preparation laboratory in Copiapo and the pulps then sent to the same company laboratory in Santiago for assaying. Samples were prepared using the following standard protocol: drying; crushing all sample to negative-one-quarter inch and passing through a secondary crusher to better than 80 per cent passing negative 10 followed by the pound key; homogenizing; splitting; pulverizing a 400 to 600 g subsample to 95 per cent passing negative 150 followed by the pound key; and a 125 g split of this sent for assaying. All samples were assayed for %CuT (total copper); %CuS (acid soluble copper). A full QA/QC (quality assurance/quality control) program, involving insertion of appropriate blanks, standards and duplicates, was employed with acceptable results. Pulps and sample rejects are stored by Marimaca Copper for future reference. Qualified person/competent person The technical information in this news release, including the information that relates to geology, drilling and mineralization, was prepared under the supervision of, or has been reviewed by Sergio Rivera, vice-president of exploration, Marimaca Copper, a geologist with more than 40 years of experience and a member of the Colegio de Geologos de Chile and of the Institute of Mining Engineers of Chile, and who is the qualified person for the purposes of National Instrument 43-101 responsible for the design and execution of the drilling program. The information in this announcement which relates to exploration results for the Pampa Medina project is based on, and fairly reflects, information and supporting documentation prepared by Sergio Rivera, VP, exploration of Marimaca, a competent person who is a member of the Comision Minera (Chilean Mining Commission), Colegio de Geologos de Chile and of the Institute of Mining Engineers of Chile. Mr. Rivera has sufficient experience that is relevant to the style of mineralization and types of deposit under consideration and to the activity being undertaken to qualify as a competent person as defined in the 2012 Edition of the Joint Ore Reserves Committee Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr. Rivera consents to the inclusion in this announcement of the matters based on his information in the form and context in which it appears. We seek Safe Harbor.