Everyday Uses of Lanthanides: The Rare Earth Elements

If you look at the periodic table, can you identify the elements known as lanthanides? Don’t worry if you can’t — they’re not an element you’ll likely encounter on your daily walk through the park. Also known as rare earth elements, these 15 elements fall between the atomic numbers 57 and 71 and have their own section on the bottom of the periodic table. What are lanthanides, and where might you encounter them in your everyday life?

Lanthanide Properties

First, you’ll want to look at the elements of the lanthanide group. Despite the group’s nickname — “rare earth elements” — these compounds aren’t all that rare. The 15 elements are as follows:

Atomic No. 57-61	Atomic No. 62-66	Atomic No. 67-71
Lanthanum	Samarium	Holmium
Cerium	Europium	Erbium
Praseodymium	Gadolinium	Thulium
Neodymium	Terbium	Ytterbium
Promethium	Dysprosium	Lutetium

The only exception to this abundance is promethium because it is produced artificially in the lab. In fact, its longest-lasting radioactive isotope only has a half-life of 18 years, which is why it doesn’t occur naturally on Earth.

Occasionally, the transition metals scandium and yttrium are included in this group. However, these were already discussed in another article where you can learn about their properties and everyday uses in depth. 

Chemical and Physical Traits of Lanthanides

While lanthanides are relatively common in the Earth’s crust, they are difficult to extract in usable quantities. These elements are bright and usually silvery until they are exposed to oxygen. They are highly reactive and may ignite when exposed to temperatures of 150-200 degrees Celcius — 302-392 degrees Fahrenheit.

Lanthanides also tarnish quickly, making them susceptible to contamination from other elements. However, not all lanthanides tarnish at the same rate. Lutetium and gadolinium, for example, can be exposed to air for long periods without tarnishing. At the same time, elements like lanthanum, neodymium and europium are highly reactive and must be stored in mineral oil to prevent tarnishing.

All members of the lanthanides group are incredibly soft. Most can be easily cut with a knife and don’t require heavy-duty tools to be removed from the Earth.

These elements aren’t considered rare because they’re hard to find. They’re rare because it is difficult to extract sufficient quantities of the pure form of each component to meet any and all industrial needs.

Real-Life Applications

Where can you encounter these rare earth elements in your daily life besides in a lab? They’re actually more prevalent than you might think. Lanthanides can be found in lamps, lasers, magnets and more. They’re also used in many manufacturing processes, including those for petroleum and steel.

Cerium

Ceres is a dwarf planet in the asteroid belt that, among other things, serves as a major setting in “The Expanse” television show. It also lends its name to the first lanthanide on our list — cerium.

Scientists found cerium in 1803, and while it only makes up 0.0046% of the Earth’s crust, it is still the most abundant of the rare earth elements on the planet. It is incredibly soft and easily scratched with metal tools and objects but has several limited applications.

You can find cerium in various minerals, including allanite, monazite, bastnasite, samarskite and cerite. Usually, monazite appears on Travancore, India’s coastlines and along Brazil’s riverbanks. Allanite is especially abundant on the West Coast of the United States, with bastnasite typically found in Southern California.

Uses for Cerium

• Carbon arc lighting: Cerium is a key component in carbon arc lights, which are ultrabright light sources popular in the motion picture industry.
• Lighter flints: Cerium is often one of the primary components in mischmetal, which you’ll find in lighter flints.
• Glass manufacturing: In the glass industry, cerium finds uses as a polishing agent and decolorizer, removing pigment from the glass. Reclaiming the cerium from glass polishing waste is possible, making it eco-friendly.

Gadolinium and Yttrium

Gadolinium and yttrium are two raw materials that are almost always found together. The same researcher discovered both in the late 1700s. Here are some uses of these elements.

Uses for Gadolinium and Yttrium

• Television phosphors: Both elements are often found in older televisions, lending color to the devices in the form of phosphors. Yttrium, in particular, creates a vibrant red shade.
• Artificial garnets: Scientists can create synthetic garnets by combining gadolinium and yttrium, but these differ from the gems you’ll wear in jewelry. Instead, they’re used in microwave technology.
• Nuclear control rods: Gadolinium is the best element on the planet for capturing neutrons, making it an excellent choice for nuclear control rods. Unfortunately, the two gadolinium isotopes that work best for this are in short supply.

Lanthanum and Samarium

Scientists discovered lanthanum almost by accident. In 1839, a Swedish chemist was looking for impurities in cerium and found an entirely new rare earth metal. Its name comes from the Greek word lanthaneia, meaning “to lie hidden.” It’s an appropriate moniker for an element that was hiding inside cerium. 

On the other hand, samarium got its name from samarskite, the mineral from which scientists extract the element. It is primarily found in monazite and bastnasite — however, impure samarium is also derived from misch metal for various purposes. 

Uses for Lanthanum and Samarium

• Absorbing hydrogen: Lanthanum can absorb massive amounts of another element. In this case, it can absorb more than 400 times its volume in hydrogen — this could be beneficial for use in hydrogen-fueled vehicles in the future. 
• Lighter flints: Like cerium, lanthanum is also a component in the mischmetal that makes up lighter flints. Most flints contain between 25-45% lanthanum. Samarium make up about 1% of these flints.
• Glass manufacturing: Lanthanum and samarium both improve glass’s alkali resistance, making it an excellent choice for manufacturing specialty lenses such as those used in cameras and telescopes.
• Petroleum refining: Zeolite crystals contain lanthanum salts, which help stabilize zeolite at high temperatures during petroleum refining. 

Erbium, Terbium and Europium

These last few rare earth elements don’t have many applications. However, erbium, terbium, and europium still have a few uses.

Uses for Erbium, Terbium and Europium

• Glass and porcelain tints: Erbium is the primary component in pink pigments for glassmaking and porcelain tints.
• Television phosphors: When exposed to electrons, terbium glows a brilliant green and is often used as a phosphor in televisions.
• Postage stamps: A little bit of europium goes a long way and allows post offices to scan stamps electronically.

The rest of the elements in this group have little to no practical application. They’re reactive and expensive to mine. You may find them in televisions as phosphors or in nuclear reactors. They’re certainly different from the kind of raw material you’ll see in your local grocery or department store.

Unearthing the Truth: The Sustainability Paradox of Rare Earths

The market size for global rare earth metals is expected to have a compounded annual growth rate of 10.2% from 2024 to 2023 — $3.39 billion to $3.74 billion. The Asia Pacific region had the highest market share at 86.14% in 2023.

One reason the world is consuming more rare earth metals is the increasing demand for electronic devices, lithium-ion battery components and other green technologies. Likewise, rapid urbanization, industrialization and digitalization across the globe have boosted the need for these raw commodities.

However, while rare earth elements — particularly lanthanides — are critical for emissions-reducing solutions for a healthier environment, a dire sustainability paradox is at play. Metal mining, especially, is the top toxic polluter in the U.S. It’s nearly impossible to extract these compounds without causing ecological damage. 

A standard extraction method involves removing topsoil and creating a leaching pool for harmful chemicals. These chemicals are used to separate the elements from ore. Unfortunately, the toxins usually enter groundwater, cause air pollution and drive erosion. Another strategy involves drilling holes into the ground and pumping chemicals into the Earth with polyvinyl chloride pipes. Yet, the residue ends up in a leaching pond, causing the same problems.

The situation can be even worse, considering rare earth elements occur near radioactive sources like thorium and uranium. The residual radioactive waste may leak into the surrounding ecosystems and contaminate vital water sources. 

According to the Harvard International Review, mining one metric ton of rare earth elements accumulates 13 kilograms of dust — about 28.7 pounds — and 9,600 to 12,000 cubic meters of waste gas. Another 75 cubic meters of wastewater is produced along with one metric ton of radioactive remnants. 

Experts are exploring ways to make extraction and processing methods of rare earths more environmentally safe and efficient. Likewise, they’re finding ways to recover these elements from waste using less harmful solvents. One solvent — hydrophobic deep eutectic solvent — can recover 96% of lanthanum and 98% of cerium. The metals were also 99.6% pure with little contamination.

Lanthanides Are Crucial for Everyday Life

You may not often consider the importance of lanthanides in your everyday life, from the sunglasses you wear to protect your eyes to the television screen you watch. These rare earth elements are everywhere. Of course, if the world continues utilizing them in consumer goods, it is crucial to approach the mining process with cutting-edge solutions and adherence to sustainability principles.

Editor’s note: This article originally published 04/06/2018. We updated it on 08/05/2020 to expand the section of Real Life Applications and again on 11/19/2024 to include information about the sustainability of rare earth element extraction.