A mysterious type of magma found within extinct volcanoes around the globe may contain large quantities of rare earth elements, critical for powering clean technologies such as electric vehicles and wind turbines, according to a report published Tuesday.

Rare earth elements like lanthanum, neodymium, and terbium play a crucial role in reducing reliance on planet-warming fossil fuels. Although these materials, known as “rare earths,” are not truly rare, they can be difficult to extract due to their low concentrations. As global demand surges, many countries are searching for new sources to reduce their dependence on China, which currently dominates the rare earth supply chain.

The study, conducted by researchers from the Australian National University (ANU) and the University of the Chinese Academy of Sciences, suggests that rare earth elements could be extracted from iron-rich magma found in extinct volcanoes. This magma, according to the study, is significantly more efficient at concentrating rare earth elements than the magma from active volcanoes.

Michael Anenburg, a research fellow at ANU and co-author of the study, said the discovery “potentially opens a new avenue for rare earth extraction.”

The research was inspired by the 2023 discovery of a vast deposit of rare earth elements in Kiruna, Sweden, a mining town with an iron-ore deposit formed around 1.6 billion years ago due to volcanic activity. This finding led researchers to explore why rare earths were concentrated in this area and whether other iron-rich volcanoes might contain similar deposits.

Because these extinct volcanoes are rare and inaccessible, the researchers created a laboratory simulation of a magma chamber using synthetic rocks. When heated to extreme temperatures in a pressurized furnace, the iron-rich magma absorbed rare earth elements from its surroundings, becoming up to 200 times more efficient at concentrating these elements than typical volcanic magma.

The findings suggest that unexplored deposits of rare earth elements could exist in extinct volcanoes worldwide, including in the United States, Chile, and Australia. Many of these locations are already mined for iron ore, offering a potential “win-win” for both mining companies and the environment, Annenberg noted.

“This approach could allow companies to extract more value from existing mines, reducing the need to disturb new locations,” he explained.

Lingli Zhou, an assistant professor specializing in energy-critical metals at Vrije Universiteit Amsterdam, praised the study for its innovative approach. “They start from the laboratory and mimic natural processes to understand how rare earths accumulate in specific areas,” she said, noting that the research could help geologists locate economically viable deposits and diversify the rare earth supply chain.

However, rare earth mining has been linked to environmental and human rights concerns, including the use of toxic chemicals that pollute soil and groundwater, as well as allegations of child labour in the supply chain. Some experts argue that recycling rare earth elements from old electronics could be a more sustainable solution.

A recent study found that recycling materials from items like old cell phones and electric vehicles could provide a large and underutilized source of rare earths, potentially reducing the need for new mining operations.

The discovery of rare earth elements in extinct volcanoes could provide a crucial new resource for clean energy technologies, but balancing environmental sustainability and ethical concerns remains a key challenge for the industry.