Global hunt for rare earth elements is underway

Rare earth elements are everywhere – in your smartphone screen, in the MRI machine at the hospital, in the battery of an electric vehicle, and even in oil and gas refining. They are a key ingredient of modern life.

As global tensions rise, so does the competition for access to these minerals. Recent headlines show the stakes: China has halted rare earth exports to the United States, and a deal was just signed to secure U.S. access to Ukraine’s mineral resources.

Despite their name, rare earth elements aren’t actually scarce; what’s rare is finding them in high enough concentrations to mine economically. These deposits are scattered unevenly across the globe and often buried deep underground, shaping who controls their production and the global supply chain.

Scientists at Tufts University are trying to better understand how and why rare earth minerals ended up where they did. Their research reveals how the movement of continents over billions of years helped form – and hide – these valuable deposits.

Supercontinents shaped rare deposits

To explain how this mineral drama began, we need to go back in time. Way back. Earth’s surface is always on the move. Over millions of years, massive landmasses shift, collide, and break apart, reshaping the planet in the process.

“Most of us are familiar with Pangea – the supercontinent that formed about 300 million years ago and that the current seven continents broke off from to form their present-day arrangement,” said Jill VanTongeren, professor and chair of the Department of Earth and Climate Sciences.

“But Pangea is only the most recent supercontinent. Throughout Earth history, there have been at least five major supercontinent cycles – periods when continents all come together and then spread back out again into different pieces. We think this process happens roughly every 500 million years.”

Where minerals begin

As these continents drifted apart, they created rifts – places where the Earth’s tectonic plates pulled away from each other. These rifting zones became birthplaces for rare earth element-rich magmas.

“As the rocks are pushed apart, they decompress, causing melting. It’s kind of like taking the lid off a soda bottle, and the bubbles rise to the surface,” said VanTongeren.

“Those early magmas contain the highest abundance of rare earth and other incompatible elements that then enter the crust, either erupting in volcanic centers or solidifying at depth.”

Some of these mineral-rich magmas cooled and stayed near the surface. Others got dragged back down into the mantle or remain buried too deep to mine with today’s technology.

A race for control resources

Today, the number of economically viable rare earth deposits is limited. China dominates the market, with nearly 70% of global production coming from its Bayan Obo mine. The U.S. has a smaller operation at Mountain Pass in California, and a few other countries have scattered deposits.

In the late 1990s and early 2000s, China flooded the market with rare earth minerals, driving down prices and shutting down other global producers. That move reshaped global dependence.

In response, the U.S. government took steps to re-establish a domestic supply. Recent investments from the 2021 Infrastructure and Jobs Act and the Department of Defense aim to restart full operations at the Mountain Pass mine, though it could take up to a decade.

There’s also hope that Ukraine’s mineral deposits could help diversify supply. But for now, their potential remains unclear.

“Political boundaries and the desire to obtain access to mineral resources have been the source of economic and military conflicts throughout human history,” said VanTongeren. “This is likely to continue as the world shifts toward green energy and a greater dependence on rare earth elements in the future.”

Hunting for mineral deposits

VanTongeren’s work tracks these mineral stories from source to surface. Her fieldwork has taken her from a ship near Antarctica to platinum mines in South Africa, Morocco’s mountains, and even a lithium discovery in Maine.

“It’s a fascinating area of study partly because it lies at the intersection of science, economics, and politics,” she said. Back on the Tufts campus, this intersection takes a more visual form.

Tufts’ secret mineral vault

Tucked into the basement of Lane Hall, the P.T. Barnum Mineral Collection offers a glimpse into the Earth’s treasures. It includes thousands of mineral specimens, some collected by Barnum himself. He was an early supporter of Tufts and a major collector of natural history in the 1800s.

“In the late 1800s, it was considered fashionable for many prominent individuals to accumulate their own natural history collections,” noted VanTongeren.

“P.T. Barnum was one of the biggest collectors of the time. His collection of animals, plants, and minerals was among the first gifts to Tufts University and part of an endowment to establish Tufts as one of the major natural history museums in the country.”

After a fire destroyed the Barnum Museum in 1975, the mineral collection moved to Lane Hall. Now, it’s about to move again – this time to Bacon Hall, the new home for the Department of Earth and Climate Sciences.

Global hunt for rare earth elements

VanTongeren hopes this new home will be more than just a storage site. She wants it to become a space that encourages curiosity and exploration, not just for scientists, but for everyone.

“My pie-in-the-sky vision is to set up a mineral gallery with both a permanent exhibit as well as pop-up exhibitions every semester highlighting minerals important for technology, related to other research at the university, or to global events,” said VanTongeren.

“I’d like to help bring back Barnum’s vision of bringing the beauty of, and an appreciation for, the natural world to campus.”

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–