You’ve likely heard a lot of chatter about “rare earth elements/minerals” lately. China and the United States jockeying for a slice of the rare earth material market. The U.S. making mineral extraction, especially of rare earths, a key condition of supporting Ukraine in its war with Russia. The race to mine rare earth minerals from sensitive, deep-sea ecosystems.
But with all the recent fuss, how rare are rare earth minerals, really? It turns out, not terribly rare.
If you consider their total abundance in the planet’s crust, some so-called rare earth minerals are actually more common than more-familiar stuff, such as lead, copper, and gold. The supposedly rare minerals—useful in all sorts of products, from smartphones to military-grade weapons—are defined as containing one or more of the 17 rare earth elements, but they can be found across the face of the globe. Their nominal rarity refers less to their overall abundance than to their habit of not occurring in dense, concentrated accretions (the way copper, iron, or gold do), making them much more costly to extract and purify.
Here are a few of the key rare earths and their median crustal abundances (MCA), a standard measure of how common they are in our planet’s outer layer.
Europium: This rare earth element was one of the earliest extracted and processed on a commercial scale in the U.S. In the early 1950s, europium helped produce fundamental chemicals needed to make new fangled color TV technology a reality. Composed of two isotopes (151EU and 153EU), naturally occurring europium is typically mined along with other rare earth elements, and it occurs in Earth’s crust at greater abundances than gold, silver, or platinum, at an MCA of about 2 parts per million. (Gold exists at about 0.004 parts per million.)
Samarium: Another useful rare earth element is samarium, which can be used in lasers capable of high-resolution microscopy or combined with cobalt to make magnets that can function at very high temperatures, an important property for radar technology used by the U.S. during the Cold War. The element samarium—which does not exist free in nature but is part of other minerals, such as monazite and florencite—is also relatively abundant, with an MCA of about 7 parts per million.
Read more: “Lithium, the Elemental Rebel”
Erbium: Erbium has an MCA of about 3 parts per million, and this rare earth element has many important uses in modern technology. Its fluorescent, pink-hued ER3+ ions can amplify light, boosting information-rich signals in fiber-optic cables, making first cheap long-distance telephony and now worldwide internet data transmission and laser surgery possible.
Cerium: The most common rare earth element is cerium. This element is just as common as copper, at an MCA of 68 parts per million. It was first used, along with another rare earth, thorium, in the 19th century in gas mantles to light European cities.
After these and other rare earth elements have been extracted, processed, and combined with other materials, they become pretty darn ubiquitous. As a matter of fact, you likely have some rare earth in your pocket, purse, desktop, or driveway right now. Rare earth minerals are used to make high-tech magnets used in electric vehicles, electronic components for micro processors and smartphones, and in glass for computer monitors and camera lenses.
As rare earths continue to make headlines, remember, they’re not so much rare as they are inconvenient to mine, purify, and make into things us modern humans use. 
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