Marimaca Copper Extends High-Grade Bornite Zone at Pampa Medina

• Step-out drilling extended the central ultra-high-grade bornite zone 300 metres to the south, returning 20 metres at 2.65% copper and 13.9 grams per tonne silver from a depth of 564 metres, including 6 metres at 6.11% copper and 24.0 grams per tonne silver.
• The same hole returned 104 metres at 1.01% copper and 4.7 grams per tonne silver from a depth of 664 metres, including 40 metres at 2.04% copper and 11.1 grams per tonne silver.
• Drilling intersected mineralisation in basement metasediments for the first time at Pampa Medina, in the deepest hole drilled to date at 1,052 metres, indicating potential for further depth extension.
• Near-surface oxide mineralisation was intersected 150 metres west of the historic Pampa oxide footprint, returning 10 metres at 0.31% copper and 2.8 grams per tonne silver from 180 metres depth.
• Marimaca Copper will host an investor webinar on Pampa Medina exploration progress on July 14, 2026, via Investor Meet Company. 

Company Overview

Marimaca Copper (TSX: MARI | ASX: MC2) is a copper company operating in Chile's Antofagasta Region. Its principal asset is the Marimaca Oxide Deposit (MOD), and its Pampa Medina discovery lies approximately 28 kilometres to the east. Pampa Medina is a manto-style copper deposit hosted in Jurassic-Triassic sedimentary units overlain by andesitic volcanics and underlain by an Upper Paleozoic metamorphic complex.

Step-Out Drilling Results

Marimaca Copper reported additional assay results from ongoing step-out drilling at the Pampa Medina deposit, which continue to extend the central high-grade sulphide zone and confirm multiple stacked manto-style copper-silver horizons across the sedimentary and volcanic sequence.    

A step-out drill 300 metres south of previously released holes extended the ultra-high-grade bornite-chalcocite zone. It returned 20 metres at 2.65% copper and 13.9 grams per tonne silver from 564 metres depth, including 6 metres at 6.11% copper and 24.0 grams per tonne silver. Deeper in the same hole, drilling returned 104 metres at 1.01% copper and 4.7 grams per tonne silver from 664 metres depth, including 40 metres at 2.04% copper and 11.1 grams per tonne silver, within which were 14 metres at 3.36% copper and 17.7 grams per tonne silver and 4 metres at 6.54% copper and 38.5 grams per tonne silver.    

The same hole also intersected near-surface oxide mineralisation 150 metres west of the historic Pampa oxide footprint, returning 10 metres at 0.31% copper and 2.8 grams per tonne silver from 180 metres depth. 

Depth Extension into Basement Metasediments     

Drilling extended mineralisation into the basement metasediments for the first time at Pampa Medina. The deepest hole drilled to date, reaching 1,052 metres, returned 660 metres at 0.41% copper and 1.8 grams per tonne silver from 386 metres depth, incorporating multiple stacked mantos. These included 98 metres at 1.21% copper and 7.6 grams per tonne silver from 386 metres depth, within which was 16 metres at 2.90% copper and 21.2 grams per tonne silver, and a deeper basement interval of 66 metres at 0.70% copper from 802 metres depth.

The company noted that the intersection in the basement metasediments indicates potential for further extension at depth. The nearby Cachorro discovery, held by Antofagasta Minerals, is primarily hosted in basement tuffs and metasediments.  

A further step-out, drilled 300 metres south, returned 30 metres at 1.26% copper and 2.6 grams per tonne silver from 440 metres depth and 32 metres at 0.85% copper and 4.4 grams per tonne silver from 506 metres depth, though the hole intersected several barren post-mineral dykes.   

Pampa Medina Geology & Sampling 

Copper at Pampa Medina was originally identified in near-surface oxide mineralisation dominated by atacamite, chrysocolla, and secondary chalcocite, and has since been identified in high-grade zones of bornite, chalcopyrite, covellite, and chalcocite that extend at depth beyond the oxide-primary transition. Elevated silver grades are present in both the oxide and sulphide zones and generally correlate with copper grade. Following the consolidation of the project area in 2024, the company reinterpreted the available geological data and developed an updated model. Its 2026 campaign targets 3 priorities: defining the high-grade central area of interest, delineating the oxide extensions, and step-out drilling to test the broader system.  

All intervals are reported as downhole lengths, with true widths estimated at approximately 80% of the reported intervals. Diamond drill core was sampled continuously at 2-metre intervals and assayed for sequential copper and multi-element analyses, including silver, under a full quality assurance and quality control programme.

Investor Webinar

Marimaca Copper will host a presentation titled "Pampa Medina Exploration Update" via Investor Meet Company on July 14, 2026, at 07:00 PT / 10:00 ET / 15:00 BST. Vice President of Exploration of Marimaca Copper, Sergio Rivera, will present alongside Chief Executive Officer Hayden Locke and President Nico Cookson. 

The presentation is open to existing and potential shareholders. Questions can be submitted in advance through the Investor Meet Company dashboard until July 13, 2026, at 09:00 BST, or during the live event. A recording will be posted on the company's website afterwards.

Next Steps 

Drilling continues across the central area of interest, with the company testing the lateral and depth extent of the system following the current delineation campaign.

Rivera frames the scope of the work ahead: 

"The area drilled to date at Pampa Medina represents only a very limited portion of the broader Sierra de Medina land package, and we are excited to continue testing the lateral and depth extent of the system."

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