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A mysterious type of magma found within extinct volcanoes scattered around the world could contain an abundant supply of rare earth elements, crucial ingredients for electric vehicles, wind turbines and other clean technologies, according to a report published Tuesday.
Rare earth elements, such as lanthanum, neodymium and terbium, are critical for helping the world break its long, destructive relationship with planet-heating fossil fuels.
These materials — so-called rare earths — are not actually that rare but can be challenging to extract as they are often found in low concentrations. As demand for them ramps up, many countries are scrambling to find new sources to break their dependence on China, which currently dominates the supply chain.
The new study “potentially opens a new avenue for rare earth extraction,” said Michael Anenburg, a research fellow at the Australian National University and a study author.
The research was inspired by last year’s discovery of an enormous deposit of rare earth elements in Kiruna in Arctic Sweden, a mining town that sits upon a huge mass of iron-ore, formed around 1,600 million years ago following intense volcanic activity.For scientists at the Australian National University and the University of the Chinese Academy of Sciences, it raised a big question: why were the rare earths there?
They wanted to understand whether this was “a geological accident, or is there something inherent about those iron-rich volcanoes that makes them rich in rare earth elements?” Anenburg told CNN.
They couldn’t visit one to find out — this type of volcano is incredibly rare. “We have never seen an iron-rich magma erupt from an active volcano, but we know some extinct volcanoes, which are millions of years old, had this enigmatic type of eruption,” Anenburg said.
So the scientists simulated a magma chamber in their lab using a synthetic rock with a similar composition to those from these extinct volcanoes, putting it into a pressurized furnace and heating it to extremely high temperatures.Once the rock melted and became “magmatic,” the iron-rich magma absorbed all the rare earth elements from its surrounding environment, according to the study, which concluded this iron-rich magma was up to 200 times more efficient at concentrating rare earths than the magma that commonly erupts from regular volcanoes.
The findings suggest there could be unexplored deposits of rare earths in extinct volcanoes across the world, including in the United States, Chile and Australia.
Many of these sites are already mined for iron-ore, making it a potential “win-win” for companies and the environment, Anenburg said. Companies can get more value from the mine and “we might no longer have to dig up resources from a new place,” he said.
The study takes an interesting approach, said Lingli Zhou assistant professor in energy critical metals at Vrije Universiteit Amsterdam. “They start from the laboratory and then try to mimic a natural environment, to understand how these rare earths could actually accumulate in a small place in the entire crust.”
It will be valuable information to geologists in the field to help them find rich, economically viable deposits which could help diversify the rare earth supply chain, she told CNN.Rare earth mining has been plagued with environmental problems because of the use of toxic chemicals which can pollute the soil and groundwater. Human rights groups have also reported allegations of human rights abuses in the supply chain, including child labor.
Some experts have suggested there should be more of a focus on recycling rare earth elements rather than mining.
A recent study found materials from old cell phones, electric vehicles and other sources could provide a huge and overlooked source of rare earths that could vastly reduce the need to mine.
Source: CNN Climate
