Marimaca Copper Unveils Massive High-Grade Expansion at Pampa Medina

Expanding the Footprint of Pampa Medina

Marimaca Copper Corp. has announced compelling new drilling results from its Pampa Medina deposit in Chile, revealing further high-grade copper and silver mineralization well beyond previous boundaries. The latest step-out holes, some located more than 600 metres west of earlier drilling, confirm the continuity of the mineralized sediment horizons and suggest a much larger system than initially defined.

The Pampa Medina deposit, situated approximately 28 kilometres east of Marimaca’s flagship oxide deposit, is characterised by manto-style copper-silver mineralization hosted within Jurassic-Triassic sedimentary units. The recent drilling campaign has intersected thick, consistent zones of copper grades averaging around 1% and higher, with silver grades adding valuable by-product credits.

A Significant Step-Up in Drilling Activity

Following the success of its 30,000-metre Phase II drilling program, Marimaca plans to dramatically increase its exploration efforts in 2026. The company intends to deploy 10 drill rigs targeting a total of 100,000 metres, subject to results-based stage-gates. This ambitious program aims to delineate high-grade sulphide corridors, infill oxide extensions, and test regional continuity of the mineralized system.

Notably, holes such as SWRD-02 returned 74 metres at 1.21% copper and 7.9 grams per tonne silver from 520 metres depth, including a higher-grade 12-metre interval at 2.07% copper and 17.2 grams per tonne silver. Other holes have demonstrated mineralization thicknesses exceeding 30 metres with copper grades above 1%, underscoring the deposit’s robust scale and grade consistency.

Comparisons to World-Class Copper Belts

CEO Hayden Locke emphasised the exceptional thickness of the mineralized sediments at Pampa Medina, noting that true thicknesses often exceed 20 to 30 metres and can surpass 100 metres in places. When compared to the renowned Kupferschiefer copper belt in Europe, Pampa Medina’s mining horizon is estimated to be more than ten times thicker on average, with some sections over fifty times thicker.

This scale, combined with comparable copper grades and slightly lower silver grades, suggests that Pampa Medina could support efficient bulk-tonnage mining methods with potentially lower unit costs. The presence of silver as a consistent by-product further enhances the deposit’s economic potential, with the company considering future opportunities to monetise silver streams.

Pending Metallurgical Insights and Next Steps

While the drilling results are promising, Marimaca has yet to complete initial metallurgical testing at Pampa Medina, and copper equivalent grades are not yet reported. The company is actively assaying remaining drill samples and plans to provide further updates as results become available.

Exploration Vice President Sergio Rivera highlighted the strengthening geological model and the ongoing efforts to define the limits of the mineralized system. The upcoming Phase III program will build on these insights, focusing on both oxide and sulphide zones to refine resource estimates and support future development planning.