Geologists Might Have Discovered One of Earth’s Most Priceless Finds — but Some Warn It’s Far Too Risky to Unearth
The Filo del Sol copper deposit in northwest Argentina has a new 2025 mineral resource estimate. The figures suggest the site could hold as much as five times more metals than earlier thought, which could place it among the largest copper deposits globally. The find also includes significant gold and silver resources, but mining it faces a range of legal and environmental hurdles.
A geological treasure revealed
Filo del Sol sits near the border between Chile and Argentina in the Atacama Desert, at an elevation of 5,000 metres in the Andes and in the eastern part of the Ring of Fire. Its geological roots go back to the Late Cretaceous period, which contributes to its industrial interest. The updated data raises previous estimates to up to 13 million tonnes of copper, 907 tonnes of gold (equivalent to 32 million ounces), and 18,600 tonnes of silver (equating to 659 million ounces). That uplift comes from analysing 400 additional exploration holes, which revealed deeper mineralisation that earlier work had missed.
Environmental and legal hurdles
The value beneath the ground is matched by a tangle of environmental and legal issues. The site is covered by Argentina’s Glacier Law, designed to protect freshwater resources by banning mining in periglacial zones (areas adjacent to or affected by glaciers). Fundación Ambiente y Recursos Naturales (FARN), an Argentine environmental NGO, has accused the Lundin Group, the US-based company leading the exploration, of breaching this law. Those claims point to potential risks for Argentina’s water supply, where glaciers provide about 70% of the drinking water. There are also concerns about groundwater use: the La Alumbrera mine, one of Argentina’s largest, uses 25 million cubic metres of water per year, roughly 34% of what the region’s population of nearly half a million consumes.
Operational and logistical hurdles to overcome
Getting minerals out of Filo del Sol will be difficult. The high altitude makes working conditions tougher, including the risk of altitude sickness for staff, and moving heavy machinery to such a remote site is a major logistical challenge. Further exploration is planned toward the deposit’s northern and southern edges, which will mean more drilling and excavation.
Mining companies in the Atacama are seeking to reduce emissions. Lundin Mining announced plans in 2022 to build high-voltage power lines to bring in renewable energy and minimise diesel use. In December 2024, Central Puerto started feasibility studies to assess how renewable energy could be transmitted to the region’s mines.
What this means for the global economy
Filo del Sol is likely to become a significant source of copper, gold and silver for sectors linked to the green-energy transition and technology industries, including aerospace and telecommunications. Jack Lundin, CEO of Lundin Mining, said: “Filo del Sol has been one of the most significant greenfield discoveries in the last 30 years and an amazing journey for all those that have been involved.”
As the project progresses, it prompts debate about balancing economic benefits with environmental protection. Global demand for the copper, gold and silver used in renewable energy and modern technology is clear, but development must consider impacts on ecosystems and water supplies. The unfolding story at Filo del Sol illustrates the need to balance industrial development with sustainable practices that protect the environment.