Marimaca Copper Corp. (ASX: MC2) is building something substantial in Chile’s copper-rich Antofagasta region. The Company holds an interest in an advanced oxide copper Project that sits within one of the world’s most productive mining districts. Recent developments show steady progress toward a construction decision.
Figure 1: Regional location map showing the Marimaca Copper Project [Source: Marimaca Copper Corp.]
The Marimaca Copper ASX story centres on a Project with established resources and clear development pathways. The Marimaca Copper Project received key environmental approval in November 2025, marking a critical milestone. For investors watching the global copper supply situation, this Chile copper mining Project offers exposure to a critical metal in a proven jurisdiction.
Environmental Approval De-Risks Marimaca Copper Project Development Path
Marimaca Copper received its Resolución de Calificación Ambiental (RCA) in November 2025 following multiple years of environmental baseline studies and stakeholder engagement. This approval materially de-risks the Project and allows the Company to progress with Sectorial (auxiliary) permits required for construction and operations.
The Project targets strong ESG outcomes, including recycled seawater sourced from Mejillones Bay, access to certified renewable electricity, and heap leach processing that delivers approximately 38% lower carbon intensity than traditional copper processing methods. There is no community land overlap, and the operation will draw on an available local workforce.
Definitive Feasibility Study Confirms Robust Project Economics
The 2025 DFS outlines steady-state production of 50,000 tonnes per annum of copper cathode over a 13-year mine life. Initial capital expenditure is estimated at US$587 million, translating to industry-leading capital intensity of approximately US$11,700 per tonne of copper production capacity.
At a copper price of US$5.05 per pound, the Project delivers a post-tax net present value of US$1.1 billion with a 39% internal rate of return and a 2.2-year payback period. At US$4.30 per pound, post-tax NPV is US$709 million with a 31% IRR. Operating costs remain competitive, with C1 cash costs of US$1.69 per pound and all-in sustaining costs of US$2.09 per pound.
Pampa Medina Discovery Adds District-Scale Growth Potential
Marimaca is progressing a 30,000-metre drilling programme at Pampa Medina, located approximately 25 kilometres from the planned processing plant. Drilling has confirmed an extensive oxide and sulphide sediment-hosted copper system with notable intercepts, including 198 metres at 0.7% copper and 70 metres at 1.03% copper.
Figure 2: Marimaca Copper Project location highlighting infrastructure access, including ports, power, water, and workforce proximity [Source: Marimaca Copper Corp.]
Mineralisation remains open at depth and along strike, offering potential to expand Project scale and extend mine life through future integration with the Marimaca Oxide Project.
Marimaca Copper Project: Simple Mining and Processing Support Economics
The Marimaca Copper ASX Project features conventional open-pit mining. Eight phases of pit development will provide consistent ore feed. Conventional truck and shovel operations will use 220-tonne haul trucks. The fleet expands from seven trucks initially to 13 by year seven.
Processing uses proven heap leach technology. Three-stage crushing achieves the target particle size. Crushed ore undergoes agglomeration and acid curing. Material stacks on four-metre-high dynamic heap leach pads. Initial construction includes 12 heap leach cells.
Figure 3: Aerial view of the Marimaca Oxide Deposit illustrating surface expression of copper mineralisation [Source: Marimaca Copper Corp.]
The solvent extraction and electrowinning facility targets 50,000 tonnes per annum of copper cathode production. The three-stage SX configuration includes one stripping and two washing stages. The 142-cell EW plant uses established technology. Phase two expansion increases tertiary crushing capacity and adds two heap leach cells.
Seven phases of metallurgical testing underpin the design. Testing addressed agglomeration characteristics, granulometry, and column height. Studies examined irrigation rates, acid consumption, and seawater compatibility. A geometallurgical model supports recovery and acid consumption assumptions.
Figure 4: Planned open-pit development phases and pit shell design for the Marimaca Oxide Project [Source: Marimaca Copper Corp.]
Resource Growth Demonstrates Exploration Success at Marimaca Copper ASX
The 2025 Mineral Resource Estimate shows 213.5 million tonnes Measured and Indicated. Average grade reaches 0.40% total copper for 854,000 tonnes of contained copper. Inferred resources add 21.2 million tonnes at 0.29% copper. This represents 93% of total resource tonnes in Measured and Indicated categories.
The Marimaca Copper Project has grown consistently since discovery. Maiden resource in 2017 totalled 146,000 tonnes of contained copper. The 2025 estimate shows 846,000 tonnes of contained copper in the Measured and Indicated categories. This represents nearly six-fold growth over eight years.
Reserve conversion reached 88% from Measured and Indicated resources. Proven reserves total 94.3 million tonnes at 0.46% copper. Probable reserves add 84.3 million tonnes at 0.37% copper. Combined reserves support the 13-year mine life in the DFS.
Figure 5: Near-mine and regional exploration targets surrounding the Marimaca Oxide Deposit [Source: Marimaca Copper Corp.]
The Chile copper mining Project includes near-mine exploration targets. Mercedes and Robles’ prospects show oxide potential. Cindy’s target sits in immediate proximity to the main deposit. These satellites could extend mine life and increase production scale.
Share Price Reflects Market Recognition of Marimaca Copper ASX Value
Marimaca Copper Corp. shares closed at $12.750 on recent trading, according to market data. The Company’s market capitalisation stands at approximately $1.52 billion. The 52-week trading range spans $9.700 to $13.100 per share.
Figure 6: Marimaca Copper Corp. (ASX: MC2) share price performance over the past year [Source: ASX]
Key shareholders include Greenstone at 21.6%, Assore at 18.9%, and Ithaki Limited at 13.6%. Mitsubishi Corporation holds 3.9%. This strategic investor base brings technical expertise and potential financing support. The Company held US$78.7 million in cash as of 30 September 2025.
What Happens Next for the Marimaca Copper Project
The Company advances detailed design and engineering work in 2026. An execution strategy for construction will be defined. Sectorial auxiliary permits align with the master schedule. Site early works pre-FID have been identified for 2026.
Long-lead items with delivery times exceeding 50 weeks will be secured. These include major equipment for crushing, leaching, and processing. Project financing workstreams are underway. Positive market conditions support a competitive financing process.
The 30,000-metre Pampa Medina drilling programme continues through 2026. This Phase II programme tests the extent of the mineralised system. Results will inform resource estimates and integration planning. The Company will also test MOD sulphide targets below the oxide deposit.
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FAQ
Q1. What is the production target for the Marimaca Copper Project?
Ans. The Project targets steady-state production of 50,000 tonnes per annum of copper cathode over a 13-year mine life, based on current Proven and Probable Reserves.
Q2. When did Marimaca Copper receive environmental approval?
Ans. Marimaca Copper received its Resolución de Calificación Ambiental (RCA) in November 2025, marking a key milestone toward construction readiness.
Q3. What are the capital costs for the Marimaca Copper Project?
Ans. Initial capital expenditure is estimated at US$587 million, equating to a capital intensity of approximately US$11,700 per tonne of copper production capacity.
Q4. Where is the Marimaca Copper Project located?
Ans. The Project is located in Chile’s Antofagasta Region, approximately 25 km from the Port of Mejillones and 40 km from Antofagasta city, with access to established infrastructure and workforce.
