Will We Run Out of Rare Earth Elements?

"They're valued for their special chemistry, which gives them particular magnetic properties and other advantages. These traits come from the unique configuration of the elements' valence electronsthe outer electrons commonly used in chemical bonds. In the rare earth elements, some of the valence electrons stay close to the atomic nucleus and tend not to interact with the atoms' outside environment, and so they rarely form bonds."

"Humans have mined about 4.5 million metric tons of rare earth elements so far, and we know of only 90.9 million metric tons left on Earth. At today's production rates, we will run out of these materials in 60 to 100 years. Efforts are underway, however, to find more deposits of the metals, which aren't actually especially rare but are difficult to extract because they are usually found in low concentrations along with other elements."

"Current mining methods are slow, energy-intensive and highly damaging to the environment. They generate acidic and radioactive waste, and they leach toxic chemicals into the ground. We have to figure out ways to do it better and cleaner, says Justin Wilson, a chemistry professor at the University of California, Santa Barbara. He and his colleagues recently tested a new way to extract rare earth elements from recycled electronic waste."

Seventeen rare-earth elements power smartphones, electric vehicles, medical devices and other technologies because of unique valence-electron configurations that produce predictable magnetic and chemical properties. Humans have mined about 4.5 million metric tons and identified roughly 90.9 million metric tons remaining, yielding an estimated supply of 60 to 100 years at current production rates. Deposits are dispersed at low concentrations, making extraction difficult. Current mining is slow, energy-intensive and generates acidic and radioactive wastes while leaching toxic chemicals. Efforts include searching for new deposits, developing cleaner mining techniques and extracting rare earths from recycled electronic waste, supported by sustained federal research funding.

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