Today, let’s take a look at interesting facts about Europium and answer the following questions: “Why Is Europium Considered A Rare Earth Element?”, and “Why Is Europium Considered A Critical Raw Material?”

For more information, check out the light rare earth elements (LREEs) as a group, the heavy rare earth elements (HREEs) as a group, and all rare earth elements (REEs). Be sure to check out all other critical raw materials (CRMs), as well.

Why Is Europium Considered A Rare Earth Element?

Europium is considered a rare earth element because it is one of the 15 lanthanide elements that constitute the core group of rare earth elements. With atomic number 63, europium is positioned between samarium (62) and gadolinium (64) in the lanthanide series, which extends from lanthanum (atomic number 57) through lutetium (atomic number 71). As a lanthanide, europium exhibits the fundamental chemical properties that define this group, though it is notable for being one of only two rare earth elements (along with cerium) that commonly exhibits multiple oxidation states. While europium typically exists in the trivalent state (Eu3+) characteristic of all REEs, it “can exist as Eu2+” under certain conditions, distinguishing it within the lanthanide family while remaining fundamentally a rare earth element.

Europium’s classification within the rare earth elements reflects its systematic position and geochemical behavior. Traditionally grouped with the light rare earth elements, which comprise “lanthanum through gadolinium (atomic numbers 57 through 64),” europium is noted by some authorities as belonging to the heavy rare earth group due to certain chemical properties. With a crustal abundance of 2.0 parts per million, europium is the least abundant of the light rare earth elements, being less common than samarium (7.05 ppm) or gadolinium (6.2 ppm), but still more abundant than silver, gold, or platinum. This relative scarcity among the light REEs makes europium particularly valuable, as evidenced by prices ranging from “$250 to $1,700/kg (for Eu2O3) over the past decade.”

Europium’s geochemical behavior aligns with the defining characteristics of rare earth elements while displaying some unique properties. Like all REEs, europium’s high charge and ionic radius generally prevent its incorporation into common rock-forming minerals, causing it to concentrate with other rare earth elements during magmatic processes. However, europium’s ability to exist as Eu2+ creates an important exception – “europium is often depleted in magmas because it is incorporated into feldspars owing to its Eu2+ valence state.” Despite this anomaly, europium invariably occurs with other rare earth elements in REE minerals including bastnäsite ((REE)CO3F), monazite ((REE,Th)PO4), and xenotime. The principle that “REEs can substitute for one another in crystal structures, and multiple REEs typically occur within a single mineral” applies to europium in its typical Eu3+ state.

The combination of europium’s position in the lanthanide series, its fundamental REE chemistry including the dominant Eu3+ state, its consistent co-occurrence with other REEs in natural deposits, and its irreplaceable role in phosphor applications firmly establishes europium as a rare earth element – one whose unique properties have driven the development of the entire rare earth industry.

Why Is Europium Considered A Critical Raw Material?

Europium is considered a critical raw material due to its absolutely irreplaceable role in display and lighting technologies, combined with its relative scarcity and extreme supply concentration. The criticality of europium is starkly demonstrated by the fact that “color cathode-ray tubes and liquid-crystal displays used in computer monitors and televisions employ europium as the red phosphor; no substitute is known.” This complete absence of alternatives means that without europium, the global display industry – encompassing televisions, computer monitors, smartphones, and all other color displays – cannot function. Additionally, europium is essential in energy-efficient lighting, where “yttrium, europium, and terbium phosphors are the red-green-blue phosphors used in many light bulbs, panels, and televisions.” The element is also “a common dopant (doping agent) for optical fibers,” making it critical for telecommunications infrastructure.

The criticality of europium is severely amplified by its scarcity and concentrated supply chain. With a crustal abundance of only 2.0 parts per million, europium is the least abundant of the traditional light rare earth elements. This scarcity translates directly into high market value, with europium oxide commanding “$250 to $1,700/kg (for Eu2O3) over the past decade,” making it one of the most valuable rare earth elements. Between 2011 and 2017, China produced approximately 84% of the world’s rare earth elements, with the United States contributing only about 4% during its limited production from 2012-2015. When China announced export restrictions in 2010 through quotas, licenses, and taxes, europium-dependent industries faced immediate crisis. The vulnerability is compounded by the fact that europium represents only a small fraction of rare earth deposits, and “deposits containing relatively high grades of the scarcer and more valuable heavy REE (HREE: Gd to Lu, Y) and Eu are particularly desirable,” highlighting europium’s exceptional status.

The strategic and historical importance of europium extends beyond current applications to its foundational role in the rare earth industry. “Early development was supported largely by the sudden demand for Eu created by the commercialization of color television” at Mountain Pass in the 1960s, demonstrating how europium single-handedly drove the development of Western rare earth mining. This pattern continues today, where europium’s high unit value helps subsidize the extraction of other rare earth elements. The widespread adoption of energy-efficient fluorescent lamps containing europium phosphors “could potentially achieve reductions in U.S. carbon dioxide emissions equivalent to removing one-third of the automobiles currently on the road,” positioning europium as critical to climate change mitigation strategies.

The combination of multiple factors establishes europium as one of the most critical raw materials for modern society. Expert panels from the National Research Council, U.S. Department of Energy, and European Commission have consistently ranked rare earth elements as having the highest “criticality” factor, with europium representing an extreme case within this group. The complete absence of substitutes for europium in red phosphors, combined with its essentiality for all color displays and energy-efficient lighting, means that europium availability directly constrains global technology production. Processing complexity adds another layer of criticality – “nearly all REE separation and refining” occurs within China, meaning even rare earth ores mined elsewhere must be sent to China to extract europium. 

The convergence of europium’s irreplaceable role in displays and lighting, its scarcity even among rare earth elements, its high value reflecting supply-demand imbalance, the concentration of both mining and processing in China, and its importance to energy efficiency goals firmly establishes europium as a critical raw material where supply disruptions would have immediate and cascading effects on global technology and climate objectives.

Interesting Facts About Europium

1. Europium is the most reactive of all rare earth elements, readily oxidizing in air and reacting violently with water, requiring storage under mineral oil or inert gas.
2. It exhibits the largest range of oxidation states among lanthanides, existing in +2 and +3 states, with Eu2+ being unusually stable for a lanthanide.
3. Europium has the lowest density (5.24 g/cm³) and is the softest of all lanthanide elements, easily cut with a knife.
4. Natural europium consists of two isotopes: Eu-151 (47.8%) and Eu-153 (52.2%), both of which are stable.
5. Europium-doped phosphors produce the red color in cathode ray tubes and LED displays, making it essential for color television and computer monitors.
6. The element exhibits unique luminescent properties due to its 4f electron configuration, producing sharp emission lines that make it ideal for anti-counterfeiting in Euro banknotes.
7. Europium has an exceptionally large neutron absorption cross-section, making it valuable as a neutron absorber in nuclear reactor control rods.
8. It possesses the second-lowest melting point (822°C) among rare earth elements, only higher than cerium.
9. Europium anomalies in geological samples serve as indicators of oxidation-reduction conditions in ancient oceans and can reveal information about Earth’s early atmosphere.
10. The element demonstrates unusual magnetic properties, becoming ferromagnetic below 90K and exhibiting complex magnetic phase transitions.
11. Europium compounds show the phenomenon of “antenna effect” where organic ligands absorb UV light and transfer energy to Eu3+ ions, resulting in intense red luminescence.
12. It has the highest electrical resistivity among rare earth metals at room temperature (90 μΩ·cm).
13. Europium-doped strontium aluminate creates the brightest and longest-lasting phosphorescent materials known, glowing for hours after light exposure.
14. The element’s 5s²5p⁶ closed-shell configuration in Eu2+ makes it behave similarly to alkaline earth metals rather than typical lanthanides.
15. Europium exhibits a unique “negative europium anomaly” in lunar rocks, providing evidence about the Moon’s formation and differentiation.
16. It has one of the largest ionic radii among trivalent lanthanides, affecting its coordination chemistry and crystal field splitting.
17. Europium-155 is used in medical imaging as a gamma-ray source for bone density measurements due to its favorable half-life (4.76 years).
18. The element shows exceptional catalytic properties in certain organic reactions due to its variable oxidation states and Lewis acid character.
19. Europium compounds exhibit the strongest ligand-field effects among lanthanides, resulting in significant spectroscopic shifts useful for studying molecular environments.
20. It demonstrates anomalous compressibility under high pressure, undergoing electronic transitions that dramatically change its physical properties at around 14 GPa.

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