Marimaca Copper Demonstrates Significant Expansion Potential with 300m Western Extension at Pampa Medina

• Hole SMRD-16 successfully extends high-grade manto-system 300m west with 70m of 1.0% Cu including 10m of 4.2% Cu
• Mineralized area now confirmed across 1.2km x 1.2km zone with extensional potential to north and west
• Proximity to existing infrastructure positions project for potential development advantages
• Underground mining opportunity identified with economic cut-off grades between 0.5-0.8% Cu
• Company advancing multi-pronged strategy: near-term MOD production, Pampa Medina development, and district-scale exploration

Marimaca Copper is a copper development company focused on advancing its portfolio of copper projects in Chile's Atacama Desert. The company's flagship asset is the Marimaca Oxide Deposit (MOD), positioned for near-term production, with significant exploration upside through the Pampa Medina and Madrugador projects. Pampa Medina is located at low altitude approximately 28km east of the Company's Marimaca Oxide Deposit (MOD) in a flat "pampa" valley within the Atacama Desert.

Drilling Results Extend High-Grade Mineralization

The latest drilling campaign at Pampa Medina has delivered significant results that expand the known mineralized footprint. Hole SMRD-16 extends the high-grade manto-system a further 300m to the west, with varying depths of the oxide to sulphide transition. The company reported multiple high-grade intersections that demonstrate the continuity and scale of the deposit.

Key results from SMRD-16 include 70m of 1.0% from 434m including: 10m of 4.2% Cu from 438m downhole within 30m of 2.1% Cu from 434m in oxide and secondary sulphide zones. Additional significant intersections comprised 116m of 0.61% Cu from 516m including: 8m of 1.8% Cu from 528m (sulphide), 10m of 1.2% Cu from 568m (sulphide), 20m of 1.1% Cu from 612m (sulphide) and 50m of 0.53% Cu from 744m including: 10m of 1.1% Cu from 782m (sulphide).

The results demonstrate the continuation of the geological model across the expanded area. SMRD-16 extends the high-grade mineralized manto 300m west along section from previously reported holes including previously announced results from Hole SMRD-13 which intersected 6m of 12.0% Cu from 594m downhole within 26m of 4.1% Cu from 580m and a broader 100m of 1.3% Cu from 580m.

Geological Model Validation & Exploration Potential

The drilling program continues to validate the company's geological understanding of the Pampa Medina system. Sergio Rivera, VP Exploration of Marimaca Copper, emphasized the significance of the results: "SMRD-16 is a further 300m step out to the west of the previously announced SMRD-12 and has intersected a similar broad zone of high-grade copper mineralization, including 70m at 1.0% and a number of discrete very high-grade zones."

The scale of the mineralized system is becoming increasingly apparent. Rivera noted: "The area of interest currently confirmed by drill intersections extends over 1.2km east-west by 1.2km north-south, with an average true thickness of between 50m to 100m. 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."

The geological setting supports this optimistic outlook. 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.

Development Strategy & Economic Considerations

Management has outlined clear development parameters for the Pampa Medina project. President and CEO Hayden Locke provided insight into the economic framework:

"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% and 0.8%, depending on copper price.With that in mind, we are targeting mineralized intersections with true widths exceeding 20m at an average copper grade of 1.0% 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."

Infrastructure Advantages & Location Benefits

The Pampa Medina project benefits from significant infrastructure advantages that could facilitate future development. Similar to the MOD, Pampa Medina's location is expected to drive significant infrastructure and permitting benefits: Proximity to other mines and associated infrastructure: 28km from the MOD, 64km from Sierra Gorda (South32/KGHM), 40km from Mantos Blancos (Capstone Copper), 77km from Spence (BHP), 54km from Antucoya (Antofagasta Minerals).

Additional location benefits include Low altitude, flat "pampa" type surface provides sufficient space for future facilities and infrastructure and Proximity to existing powerlines, water pipelines, major ports and regional populations. The permitting environment appears favorable with 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.

Strategic Context & Corporate Objectives

The Pampa Medina results support Marimaca's broader strategic objectives. CEO Locke outlined the company's multi-faceted approach:

"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."

The company's three-pronged strategy encompasses multiple development phases.

"With the upcoming release of the MOD DFS, our strategy remains multi-pronged: 1) deliver a near-term, low-cost 50ktpa 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."

Ongoing Exploration Program

The company is executing an extensive drilling program to further define the resource potential. The Company is executing a 10,000m extensional drilling program with three rigs currently on site. The exploration strategy is focused on high-potential areas. The favourable mineralized stratigraphic sequence is now defined by drilling across a 1.2km x 1.2km area at the Pampa Medina deposit and remains open – extensional drilling will focus on the north and the west.

Rivera indicated the next phase of exploration activities:

"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."

Technical Specifications & Methodology

The drilling program follows industry-standard protocols with comprehensive quality assurance measures. True widths are estimated as 95% of reported intervals, based on down-hole bedding and structural measurements. DDH holes were sampled on a 2m continuous basis, halved by a conventional core splitter on site with one half sent to the Andes Analytical Assay preparation laboratory in Copiapó and the pulps then sent to the same company laboratory in Santiago for assaying.

Quality control procedures ensure data reliability. A full QA/QC 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.

For Investors

Marimaca Copper's latest drilling results at Pampa Medina demonstrate significant progress in expanding the known high-grade copper mineralization. The 300m western extension validates the geological model and supports the potential for a large-scale underground mining operation. With economic cut-off grades achievable at current intersections, proximity to existing infrastructure, and a favorable permitting environment, Pampa Medina represents a meaningful growth opportunity within the company's development pipeline.

The results position Marimaca to advance its multi-phase strategy of near-term production through MOD while developing district-scale exploration potential through Pampa Medina and Madrugador. For investors, the combination of near-term cash flow generation potential and longer-term resource expansion provides a balanced investment proposition in a tier-one copper jurisdiction. The ongoing 10,000m drilling program and planned infill campaign should provide additional data points for resource estimation and development planning over the coming quarters.