Large-Scale Copper System at Pampa Medina Expands Marimaca Copper's Resource Base

• Marimaca Copper has identified a large sediment and volcanic hosted manto copper system at Pampa Medina spanning approximately 5km by 4km, with potential for extensions in all directions.
• The company's re-interpretation of data suggests Pampa Medina may be the central part of a larger system genetically linking multiple deposits, including Madrugador, Pampa Medina, Sierra Valenzuela, and Pampa Norte.
• Five reconnaissance exploration holes, combined with historical drilling review, reveal consistent broad zones of oxide copper mineralization in the same stratigraphic horizon across the project area.
• The drilling program confirmed the company's exploration model, showing that historical drilling was often not deep enough to target productive sedimentary units containing significant mineralization.
• Marimaca is planning a significantly expanded drilling program for the remainder of 2025, including both reverse circulation and diamond drilling to identify system limits and test deeper units for primary copper mineralization.

Marimaca Copper Corp. (TSX:MARI) is a copper exploration and development company with its flagship Marimaca Oxide Deposit (MOD) located in northern Chile. The company focuses on developing copper projects in one of the world's premier mining jurisdictions. The recently announced findings at Pampa Medina, situated approximately 25km from the MOD, represent a potential significant expansion of the company's resource base in the region. Marimaca Copper is listed on the Toronto Stock Exchange and has a portfolio of copper exploration and development assets in Chile.

Extensive Mineralized System

Marimaca Copper released the results from its re-interpretation of data at the Pampa Medina Project Area, which incorporates the Pampa Medina and Madrugador deposits along with the newly identified Pampa West oxide zone. This comprehensive review, combined with results from five broad reconnaissance exploration holes, has revealed consistent zones of oxide copper mineralization across an area measuring approximately 5km by 4km.

The company's exploration team has developed a new geological interpretation suggesting that Pampa Medina may actually be the central part of a much larger manto system that genetically links several deposits previously thought to be separate. These include Madrugador, Pampa Medina, Sierra Valenzuela (owned by Antofagasta Minerals), and Pampa Norte.

Sergio Rivera, VP Exploration at Marimaca Copper, commented:

"Our extensive reviews of existing data, our geophysical campaigns and the results from our initial step out discovery campaign indicate Pampa Medina is likely to be part of a much larger manto system, which extends at least 5km east to west and more than 4km north and south. We are excited about both the continuity of mineralization in the productive sedimentary and tuff horizons and the large-scale mineralizing events which have impacted them across this area."

Drilling Results Confirm Exploration Model

The recent drilling program was designed to identify the limits of the mineralized horizon and has provided significant insights into the geological structure of the area. The program included reconnaissance holes that confirmed the company's exploration model, which had hypothesized that much of the historical drilling was not deep enough to effectively target the productive sedimentary units where substantial mineralization is found.‍

The results along with historical drilling data from Pampa Medina Main, Madrugador, and Pampa Medina West, suggest substantial mineralization across the project area. Historical drilling at Pampa Medina Main, for example, includes intersections such as 122m at 1.61% CuT from 199m (DDHSM-06) and 117m at 1.15% CuT from 142.5m (DDHSM-04). Full results can be found in company's press release.

Exploration Strategy

The Pampa Medina deposit is characterized as a manto-style copper deposit primarily hosted in Lower Jurassic sedimentary units, including sandstones and black shales. These are overlain by Jurassic andesitic volcanics and underlain by a Paleozoic to Triassic complex of metasediments and intrusions, which also host significant mineralization.

The copper mineralization occurs in various forms across the stratigraphic sequence:

• Upper units of sandstones and volcaniclastics: Dominated by oxide copper minerals, especially atacamite and chrysocolla
• Underlying black shale unit at Pampa Medina Main: Significant oxide copper presence
• Upper andesitic volcanics at Madrugador: Hosts oxide mineralization
• Basement tuffs and metasediments: Transition to primary chalcopyrite and bornite mineralization

Rivera further noted:

"Our exploration model, which hypothesised that the majority of the historical drilling was not deep enough to targeting the productive sedimentary units, has been confirmed and we see numerous opportunities for further discovery and extension from our existing deposits."

This improved understanding of the stratigraphic sequence and mineralization patterns is guiding the company's exploration strategy, which now includes testing deeper zones for primary copper mineralization and exploring potential extensions of near-surface oxide mineralization.

Expanded Exploration Program Planned

Hayden Locke, President and CEO of Marimaca Copper, emphasized the reinterpretation of the previously separate deposits as parts of a single, large-scale mineralized system:

"This is the first time that the Pampa Medina system has been largely consolidated under one operator, and as such the first time that all available geological information has been consolidated and reviewed as one. While previous interpretations considered each of our identified zones as separate and distinct deposits, we are excited about the potential for Pampa Medina to rather represent a single, large scale mineralised system."

Based on these encouraging results, Marimaca is considering alternatives for a significantly expanded drilling program for the remainder of 2025. This program would include both reverse circulation (RC) and diamond drilling, with three main objectives:

1. Continue step-out drilling to identify the limits of the mineral system
2. Test deeper units for primary copper mineralization
3. Delineate areas for potential extensions of near-surface oxide mineralization

Locke expressed optimism about both near-term and long-term prospects:

"With the Pampa Norte Extension we see a strong potential for additional leachable mineralisation in the short term, and we will move to a de-lineation program later this year. In the longer term, the potential for a large scale discovery is very much intact and we intend to test our exploration model thoroughly."

Marimaca Copper's re-interpretation of data at Pampa Medina, along with the results from its reconnaissance drilling program, has revealed the potential for a much larger copper mineral system than previously recognized. The company's exploration model, which suggested that historical drilling was often not deep enough to effectively target the productive sedimentary units, has been validated by recent findings.

For investors considering Marimaca Copper, these developments represent potentially significant value creation through resource expansion and exploration upside. The planned expanded drilling program for the remainder of 2025 will be crucial in determining the full extent and economic potential of this large-scale manto copper system. With both near-surface oxide opportunities and deeper primary copper targets identified, Marimaca appears positioned to pursue both short-term and long-term growth strategies at Pampa Medina while advancing its flagship Marimaca Oxide Deposit.

Investment Implications

For investors, the discovery of this extensive manto system at Pampa Medina presents several potential implications:

1. Resource Expansion Potential: The identification of a large, connected mineral system could significantly increase Marimaca's resource base beyond its flagship Marimaca Oxide Deposit.
2. Exploration Upside: The confirmation that historical drilling often did not reach the productive sedimentary units suggests substantial exploration upside as deeper targets are tested.
3. Near and Long-Term Growth: The company has identified both near-term opportunities for additional leachable mineralization and longer-term potential for a large-scale discovery, providing a pipeline for growth.
4. Geological Understanding: The improved understanding of the stratigraphic sequence and mineralization patterns should enhance the efficiency and success rate of future exploration activities.
5. Operational Synergies: With Pampa Medina located approximately 25km from the Marimaca Oxide Deposit, there may be potential operational synergies between the projects.

As with all exploration projects, investors should recognize the inherent risks and uncertainties involved, including the possibility that future drilling results may not meet expectations or that economic challenges could impact development timelines. However, the systematic approach demonstrated by the company's technical team and the quality of intersections reported to date suggest a methodical and promising exploration program that warrants continued attention from the investment community.