Can We Extract Rare Earth Elements More Cleanly? New Methods and Global Challenges

Overview

Seventeen chemical elements—commonly called rare earths—are critical to modern electronics, electric vehicles, medical devices and many other technologies. Their distinctive magnetic and chemical behaviors come from the arrangement of valence electrons (notably those in the 4f shell), which gives these elements predictable and useful properties.

How much is left?

To date, humans have mined roughly 4.5 million metric tons of rare earth elements, and geologists estimate about 90.9 million metric tons remain in the Earth. At current production rates, those known reserves would last roughly 60–100 years, though ongoing exploration could identify additional deposits.

Why extraction is difficult

Rare earth elements are not especially scarce in the crust, but they typically occur in low concentrations and are mixed with other minerals, making economically viable deposits uncommon. The most commonly mined ore is bastnaesite, which contains higher concentrations of lanthanum, cerium and neodymium.

Current mining and processing methods

Mining and refining rare earths is a multistep, energy-intensive process that often causes significant environmental damage. Two common approaches are:

• Open-pit mining: Ore is excavated, transported to leaching ponds and treated with chemicals to separate metals. Environmental risks include leaks from leaching ponds, contaminated groundwater, toxic solid and liquid wastes, and dust and gas emissions.
• In situ leaching: Reagents are pumped directly into the ground to dissolve target elements for recovery. This method can reduce surface disturbance but carries high risk of aquifer contamination from toxic chemicals.

After extraction, ores undergo a series of chemical separation and refining steps that are resource- and energy-intensive. Overall, producing one ton of rare earth elements can generate thousands of tons of hazardous by-products and radioactive residues.

Global supply and geopolitics

China has supplied most of the world’s mined rare earths and currently holds the largest known reserves, followed by countries such as Brazil, India and Australia. The United States’ primary domestic source is the Mountain Pass deposit in California. Rising demand has prompted many nations to search for new deposits and to diversify supply chains.

Cleaner alternatives and recycling

Researchers are developing cleaner extraction methods and improving recycling. Promising avenues include greener chemical reagents, biometallurgy (microbes that selectively extract metals), and urban mining—recovering rare earths from electronic waste. For example, teams led by university researchers have begun demonstrating techniques to recover rare earths from recycled electronics, which could cut the need for primary mining if scaled up.

"We have to figure out ways to do it better and cleaner,"

— Justin Wilson, Chemistry Professor, University of California, Santa Barbara

Outlook

Transitioning to cleaner extraction and robust recycling will require sustained public and private investment, improved regulations, and international cooperation. Progress is possible, but scaling lab methods to industrial levels and reducing environmental harm remain urgent challenges.

Conclusion

Rare earth elements underpin many modern technologies, but current mining and refining practices impose heavy environmental costs. Combining new extraction technologies, aggressive recycling, and diversified supply chains offers the best path toward meeting demand while reducing harm to people and ecosystems.