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

Dysprosium 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 66, dysprosium is positioned between terbium (65) and holmium (67) in the lanthanide series, which extends from lanthanum (atomic number 57) through lutetium (atomic number 71). As a lanthanide, dysprosium exhibits all the characteristic chemical properties that define this group, including the typical trivalent oxidation state (Dy3+) and an ionic radius that follows the systematic “lanthanide contraction” pattern. As noted in the classification, “the heavy REEs comprise terbium through lutetium (atomic numbers 65 through 71),” firmly establishing dysprosium as a member of the heavy rare earth element subgroup.

Dysprosium’s geochemical behavior perfectly exemplifies the characteristics of rare earth elements. Like all REEs, dysprosium possesses a high charge (+3) and an ionic radius that prevents its incorporation into common rock-forming minerals during crystallization. Yttrium, which is grouped with the heavy rare earth elements, “has both atomic and ionic radii similar in size to those of terbium and dysprosium,” illustrating dysprosium’s position in the systematic progression of ionic sizes. With a crustal abundance of 5.2 parts per million, dysprosium is more abundant than other heavy rare earth elements like terbium (1.2 ppm) or holmium (1.3 ppm), yet still follows the pattern where heavy REEs are less abundant than light REEs. Despite being more common than silver, gold, or platinum, dysprosium rarely concentrates into economically viable deposits.

Dysprosium invariably occurs with other rare earth elements in nature, demonstrating the fundamental principle that “REEs can substitute for one another in crystal structures, and multiple REEs typically occur within a single mineral.” It is found particularly in minerals that accommodate heavy rare earth elements, such as xenotime ((Y,HREE,Th,U)PO4), where the chemical formula specifically indicates that HREEs including dysprosium can substitute for yttrium. In major rare earth deposits, dysprosium follows predictable distribution patterns – at Mountain Pass, California, the combined content of all heavy REEs from europium through lutetium plus yttrium totals only 0.4% of the rare earth oxides, while it reaches higher concentrations in China’s ion-adsorption clay deposits, which are “the world’s primary source of the heavy REEs.” Dysprosium is one of “six REE ions Gd3+ through Tm3+” that “have unusually large magnetic moments, owing to their several unpaired electrons,” making it essential for high-performance magnetic applications.

The combination of dysprosium’s position in the heavy lanthanide series, its characteristic REE chemistry including the Dy3+ oxidation state, its systematic ionic radius similar to yttrium, its invariable co-occurrence with other REEs in specialized minerals, and its critical role in high-performance magnets unequivocally establishes dysprosium as a rare earth element essential to modern technology.

Why Is Dysprosium Considered A Critical Raw Material?

Dysprosium is considered a critical raw material due to its irreplaceable role in high-performance permanent magnets essential for clean energy and defense technologies, combined with extreme supply concentration in China. The criticality of dysprosium stems from its unique function: “dysprosium is of particular importance because substituting it for a small portion of neodymium improves high-temperature performance and resistance to demagnetization.” This property makes dysprosium indispensable for “demanding applications as electric motors for hybrid cars and wind turbines,” where magnets must maintain their strength under extreme heat and stress conditions. Without dysprosium, the permanent magnets in wind turbine generators and electric vehicle motors would fail at operating temperatures, making these clean energy technologies impossible. Additionally, dysprosium is used in defense applications including jet engines and missile guidance systems where temperature stability is critical.

The extreme supply vulnerability of dysprosium amplifies its criticality. Between 2011 and 2017, China produced approximately 84% of the world’s rare earth elements overall, but for heavy rare earth elements like dysprosium, China’s dominance is nearly absolute. China’s ion-adsorption clay deposits are “the world’s primary source of the heavy REEs,” and these deposits in southern China represent virtually the only economically viable source of dysprosium globally. With a crustal abundance of 5.2 parts per million, dysprosium is scarce even among rare earth elements. At Mountain Pass, California, the combined content of all heavy REEs from europium through lutetium plus yttrium totals only 0.4% of the rare earth oxides, making Western sources incapable of producing meaningful quantities of dysprosium. When China announced export restrictions in 2010, dysprosium oxide prices surged from $261 to $410 per kilogram, demonstrating extreme market vulnerability.

The strategic importance of dysprosium extends across the entire clean energy transition and advanced defense systems. The global shift to renewable energy depends heavily on dysprosium – large wind turbines require generators with “strong permanent magnets composed of neodymium-iron-boron” enhanced with dysprosium for thermal stability. Similarly, the electrification of transportation relies on dysprosium-containing motors that can withstand the heat generated in electric and hybrid vehicles. The Department of Defense has identified rare earth elements as critical for “jet fighter engines and other aircraft components, missile guidance systems, electronic countermeasures, underwater mine detection, anti-missile defense,” with dysprosium being essential for applications requiring high-temperature magnetic stability. The fiscal year 2024 National Defense Stockpile plan specifically includes dysprosium acquisitions, reflecting official recognition of its strategic importance.

The combination of multiple critical factors establishes dysprosium as one of the most critical raw materials for advanced economies. 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 heavy rare earth elements like dysprosium representing extreme cases of supply risk. The processing challenge compounds the criticality – “nearly all REE separation and refining” occurs within China, meaning even if dysprosium-containing ores were found elsewhere, they would require Chinese facilities for extraction. The complete absence of substitutes for dysprosium in high-temperature permanent magnets, combined with its enablement of both clean energy infrastructure and defense technologies, creates a situation where dysprosium availability directly constrains global climate goals and national security capabilities. With viable deposits limited to Chinese ion-adsorption clays, processing concentrated in China, and demand growing exponentially from clean energy adoption, dysprosium represents perhaps the most critical bottleneck in the transition to sustainable energy and the maintenance of advanced defense systems.

Interesting Facts About Dysprosium

1. Dysprosium has the highest magnetic susceptibility of any element at room temperature, making it extremely responsive to magnetic fields even without being magnetized itself.
2. Its name derives from the Greek word “dysprositos” meaning “hard to get,” reflecting the extreme difficulty early chemists faced in isolating it from other rare earth elements.
3. Dysprosium metal is so soft it can be cut with a knife, yet when alloyed with other metals it dramatically increases their strength and magnetic properties.
4. Unlike most elements, dysprosium exhibits two distinct crystal structures at atmospheric pressure – a close-packed hexagonal structure at room temperature that transforms to body-centered cubic at 1381°C.
5. It has an unusually high thermal neutron absorption cross-section (994 barns for Dy-164), making it valuable for nuclear reactor control rods where precise neutron absorption is critical.
6. Dysprosium exhibits the strongest magnetostriction of any rare earth element, meaning it physically changes shape in response to magnetic fields more than any of its neighbors.
7. The element forms an unusual oxide layer when exposed to air – initially turning a bright metallic silver to a yellowish tinge, then developing a spalling oxide coating that flakes off, continually exposing fresh metal.
8. Dysprosium-iron compounds (Dy₂Fe₁₇) exhibit giant magnetostrictive properties at room temperature, expanding or contracting by up to 2,000 parts per million in magnetic fields.
9. It possesses seven naturally occurring isotopes, more than most rare earth elements, with Dy-164 being the most abundant at 28.26%.
10. The element’s magnetic moment of 10.6 Bohr magnetons is the highest of all elements, resulting from its seven unpaired 4f electrons.
11. Dysprosium fluorescence under UV light produces an intense yellowish-green glow, distinct from other rare earth elements’ fluorescent signatures.
12. Its Curie temperature (the point where it loses ferromagnetic properties) is unusually low at -188.2°C (85 K), transitioning from ferromagnetic to paramagnetic behavior.
13. Dysprosium forms the most thermally stable nitride (DyN) among rare earth elements, remaining stable up to 2,000°C in inert atmospheres.
14. The element exhibits complex magnetic phase transitions, showing antiferromagnetic ordering between 85 K and 179 K, then becoming paramagnetic above 179 K.
15. Dysprosium has an exceptionally high boiling point of 2,567°C, the third-highest among the lanthanides after lutetium and thulium.
16. Its electrical resistivity shows unusual temperature dependence, increasing linearly with temperature in the paramagnetic region but showing complex behavior in magnetic transition regions.
17. Dysprosium-doped materials can produce white light LEDs without phosphors by combining its yellow emission with blue LED chips, a unique property among rare earths.
18. The element forms organometallic compounds with unusually high coordination numbers (up to 10), more than most transition metals can achieve.
19. Dysprosium exhibits the phenomenon of “magnetic refrigeration” more efficiently than most elements, cooling when demagnetized adiabatically due to the magnetocaloric effect.
20. Its nuclear properties include a rare double beta decay in Dy-156 with a half-life of over 10¹⁸ years, one of the longest directly measured half-lives of any isotope.

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