Hidden in the Earth’s crust, scattered so thinly that early chemists dismissed them as curiosities, lie seventeen elements that would reshape our modern world. The rare earth elements—neither particularly rare nor earths—began their journey to prominence in a Swedish quarry over two centuries ago, where a curious black rock would launch one of chemistry’s most challenging detective stories.

What started as an academic puzzle for 18th-century mineralogists has evolved into the foundation of our technological civilization. These elements, with names that sound like they belong in a fantasy novel—yttrium, gadolinium, promethium—power everything from the phone in your pocket to the MRI machine that peers inside your body. They make possible the green revolution of wind turbines and electric vehicles, enable the invisible infrastructure of global telecommunications, and push the boundaries of what’s possible in medicine and manufacturing.

Yet for all their importance, the rare earth elements remain largely unknown to the public. Their story is one of scientific perseverance, geopolitical intrigue, and technological revolution—a tale that spans from candlelit laboratories to international trade wars, from the discovery of radioactivity to the race for sustainable energy. This is the complete history of how seventeen obscure elements became the most strategically important materials of the 21st century.

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). 

Read about the use of rare earths in quantum computing here.

A Complete History Of The 17 Rare Earth Elements

The story of the rare earth elements begins in the late 18th century with two pivotal discoveries in Sweden. In 1787, Carl Axel Arrhenius discovered a black mineral near Ytterby that would eventually yield yttrium and several other rare earths. Shortly after, in 1794, Johan Gadolin analyzed this mineral and discovered yttria, marking the first identification of a rare earth compound. Meanwhile, at the Bastnäs mine, another mineral called cerite was discovered, which would later yield cerium in 1803—the first individual rare earth element to be isolated, discovered simultaneously by Berzelius/Hisinger in Sweden and Klaproth in Germany.

The 19th century saw a cascade of discoveries as chemists developed increasingly sophisticated separation techniques. Carl Gustaf Mosander emerged as a pioneering figure, discovering lanthanum (1839), and separating what he called “didymium”—later revealed to be a mixture of neodymium and praseodymium. He also split yttria into three components, discovering terbium and erbium (1843). The period from 1878-1886 was particularly fruitful, with the discoveries of scandium, ytterbium, holmium, thulium, samarium, gadolinium, and dysprosium. Carl Auer von Welsbach’s separation of didymium into neodymium and praseodymium in 1885 demonstrated the complex nature of these seemingly simple substances.

The early 20th century brought the final discoveries and crucial industrial applications. Europium was confirmed in 1901, and lutetium was independently discovered by three researchers in 1907. The missing element 61, promethium, remained elusive due to its radioactive nature until it was finally produced artificially at Oak Ridge in 1945. Meanwhile, Welsbach’s invention of the gas mantle (1891) and ferrocerium (1903) marked the first major commercial applications of rare earths, with his companies selling 300 million cerium gas lamps by 1913.

The post-WWII era revolutionized rare earth separation through ion-exchange chromatography, pioneered by Frank Spedding at Iowa State. This breakthrough enabled kilogram-scale production of pure rare earths by 1954. The 1960s-1980s witnessed explosive growth in applications: europium transformed color television with red phosphors, yttrium-aluminum garnets enabled the first lasers, and the discovery of samarium-cobalt (1966) and neodymium-iron-boron (1982) magnets revolutionized everything from computer hard drives to wind turbines.

Modern applications have expanded into cutting-edge technologies and medicine. Erbium-doped fiber amplifiers (1987) became the backbone of global telecommunications, enabling the internet age. Medical applications flourished with gadolinium MRI contrast agents (1988), yttrium-90 microspheres for liver cancer (1983), and holmium lasers for prostate surgery (1994). The 21st century has seen lutetium-177 approved for cancer treatment (2018, 2022) and ytterbium optical clocks achieving unprecedented precision for next-generation timekeeping.

The geopolitics of rare earths has become increasingly critical as China emerged as the dominant producer, controlling over 95% of global supply by 2010. This monopoly triggered a supply crisis when China restricted exports, causing dysprosium prices to spike to $1,400/kg in 2011. In response, Western nations have scrambled to restart domestic production—Mountain Pass mine reopened in 2018, Australia developed new mines, and Japan discovered massive seabed deposits near Minamitori Island containing a 420-year supply of terbium. As demand for clean energy technologies and advanced electronics continues to surge, with the NdFeB magnet market alone projected to reach $19.3 billion by 2026, securing rare earth supplies has become a strategic priority for nations worldwide.

Chronology

• 1751 – Swedish mineralogist Axel Fredrik Cronstedt discovered cerite at Bastnäs mine, Sweden, which would eventually yield cerium, lanthanum, and other rare earth elements
• 1782 – Carl Wilhelm Scheele received cerite samples from Wilhelm Hisinger for analysis but failed to recognize it contained cerium
• 1787 – Swedish army officer Carl Axel Arrhenius discovered ytterbite (later renamed gadolinite) near Ytterby, Sweden, containing yttrium, ytterbium, and other rare earth elements
• 1789 – Johan Gadolin began analyzing the mineral specimen sent by Arrhenius
• 1794 – Johan Gadolin analyzed ytterbite and discovered yttria, a new oxide containing multiple rare earth elements, constituting 38% of the mineral‘s weight
• 1797 – Anders Gustaf Ekeberg confirmed Gadolin’s discovery and named the oxide “yttria” after Ytterby village
• 1801 – Giuseppe Piazzi discovered asteroid Ceres, future namesake for cerium
• 1802 – Martin Klaproth named the mineral gadolinite after Johan Gadolin
• 1803 – Jöns Jakob Berzelius and Wilhelm Hisinger discovered cerium in cerite at Bastnäs; Martin Heinrich Klaproth independently discovered cerium in Germany; both named it after asteroid Ceres
• 1804 – Louis Nicolas Vauquelin confirmed cerium discovery and studied cerite extensively
• 1825 – Carl Gustaf Mosander prepared metallic cerium by reducing cerium chloride with potassium
• 1828 – Friedrich Wöhler first isolated impure metallic yttrium
• 1839 – Carl Gustaf Mosander discovered lanthanum in cerium nitrate, naming it from Greek “lanthanein” (to lie hidden); began systematic analysis of mixed rare earths
• 1840 – Mosander separated cerium oxide into pure cerium oxide, lanthanum oxide, and “didymium”
• 1841 – Mosander announced discovery of didymium, later proven to be a mixture of neodymium and praseodymium
• 1842 – Mosander began separating yttria into three oxides
• 1843 – Mosander separated yttria into yttria, terbia, and erbia, discovering terbium and erbium; reported discoveries at British Association meeting in Cork, Ireland
• 1847 – Heinrich Rose described samarskite mineral from Ural Mountains
• 1853 – Jean Charles Galissard de Marignac observed samarium spectroscopically in didymia
• 1854 – James Simpson reported cerium nitrate suppressed vomiting, especially morning sickness
• 1860 – Marc Delafontaine reversed Mosander’s naming of terbium and erbium due to confusion; Bastnäsite replaced monazite as primary cerium source
• 1864 – Marc Delafontaine proved yttrium, terbium, and erbium were separate elements using spectroscopy
• 1869 – Dmitri Mendeleev predicted “ekaboron” (scandium); included didymium in periodic table despite it being a mixture
• 1874 – Per Teodor Cleve predicted didymium contained multiple elements
• 1875 – William Francis Hillebrand and Thomas Norton first isolated pure metallic cerium electrically
• 1876 – Lars Fredrik Nilson discovered scandium in euxenite and gadolinite at Uppsala University
• 1877 – Names erbia and terbia permanently switched due to confusion
• 1878 – Marignac discovered ytterbium by separating it from erbia; Delafontaine and Soret discovered holmium (“Element X”) at Geneva; Cleve independently discovered holmium at Uppsala
• 1879 – Cleve discovered thulium by separating it from erbia; Lecoq de Boisbaudran discovered samarium from didymium concentrates; Nilson confirmed scandium matched Mendeleev’s predicted ekaboron
• 1880 – Marignac discovered gadolinium in gadolinite and cerite
• 1881 – No satisfactory method existed to separate erbia from terbia
• 1882 – Bohuslav Brauner showed didymium varied by mineral source
• 1885 – Carl Auer von Welsbach invented gas mantle with Actinophor; separated didymium into neodymium and praseodymium; William Crookes discovered unusual spectral line in samarium
• 1886 – Lecoq de Boisbaudran discovered dysprosium after 30+ separation attempts; Marignac prepared pure terbium and isolated gadolinium oxide
• 1887-1889 – Welsbach’s first gas mantle company failed due to green-tinted light
• 1890 – Welsbach discovered thorium dioxide superior for gas mantles; Lecoq de Boisbaudran observed unknown spectral lines suggesting europium
• 1891 – Welsbach perfected gas mantle with 99% thorium dioxide, 1% cerium dioxide
• 1892 – Welsbach’s improved gas mantles spread throughout Europe; Lecoq de Boisbaudran confirmed europium spectral lines
• 1896 – Eugène-Anatole Demarçay investigated europium in samarium; Thulium oxide cost $20/gram
• 1898 – Welsbach produced Auer-Oslight; Crookes misidentified “victorium”; Thulium reached $13,300/kg
• 1901 – Demarçay isolated europium and pure samarium oxide; 50 tonnes/year holmium oxide produced globally
• 1902 – Welsbach’s cerium metal-filament bulb launched; Brauner predicted promethium
• 1903 – Welsbach patented ferrocerium; Muthmann isolated metallic samarium; Three mines produced scandium
• 1905 – Urbain and James independently isolated pure erbium oxide; Urbain disproved “victorium”; established 15 rare earth metals
• 1906 – Urbain prepared pure dysprosium fraction; Eberhard published terbium spectroscopy
• 1907 – Urbain, Welsbach, and James independently discovered lutetium; priority given to Urbain’s “lutecium”; Welsbach formed Treibacher Chemische Werke
• 1909 – International Commission adopted lutetium as official name
• 1910 – Ronson released first lighter using ferrocerium with praseodymium
• 1911 – Holmberg isolated pure metallic holmium; James obtained pure thulium using 15,000 purification operations
• 1913 – Welsbach’s companies sold 300 million cerium gas lamps
• 1914 – Henry Moseley confirmed missing element 61 (promethium); assigned holmium atomic number 67
• 1920 – Large-scale mischmetal production began (50% cerium)
• 1923 – Kremers and Stevens produced pure lanthanum metal
• 1924 – Luigi Rolla and team claimed element 61 discovery (“florentium”)
• 1925 – Kremers isolated pure neodymium metal
• 1926 – Hopkins team claimed element 61 discovery (“illinium”); Debye and Giauque proposed magnetocaloric effect theory
• 1927 – Florentium/illinium debate unresolved; Leo Moser began rare earth glass experiments
• 1928 – Moser developed Heliolit glass (praseodymium-neodymium mix)
• 1929 – Klemm and Schuth prepared ytterbium(II) compound; Moser introduced rare earth glasses at Leipzig
• 1930 – Moser’s neodymium “Alexandrite” glass widely copied; 5% neodymium oxide glasses commercialized
• 1931 – Pure praseodymium metal first produced
• 1932 – Mary Elvira Weeks published rare earth discovery history; Zippo founded using ferrocerium
• 1933 – Giauque and MacDougall achieved 0.25 K using gadolinium sulfate
• 1934 – Klemm and Bommer prepared pure erbium; Mattauch’s isobar rule confirmed promethium unstable
• 1935 – Trombe isolated metallic gadolinium, discovered ferromagnetism; Klemm and Bommer isolated dysprosium
• 1936 – Klemm and Bommer obtained metallic thulium and holmium
• 1937 – Klemm and Bommer produced ytterbium metal; Fischer et al. produced metallic scandium; liquid-liquid extraction developed
• 1938 – Law et al. proposed “cyclonium”; Europium-152 discovered
• 1939 – Bommer isolated metallic holmium; 60-inch cyclotron used for promethium attempts
• 1940s – Soviet scandium research began; Ion exchange techniques developed
• 1942 – Meggers discovered thulium fundamental energy interval
• 1943 – Primo Levi bartered ferrocerium at Auschwitz; Cerium production expanded
• 1945 – Ames Laboratory produced 437 pounds pure cerium; Webb traced cerium-141 to Trinity test; Marinsky, Glendenin, and Coryell produced promethium at Oak Ridge
• 1947 – Oak Ridge announced promethium discovery; Spedding published ion-exchange separation methods
• 1948 – U.S. recommended name “promethium”; First promethium compounds shown
• 1949 – IUPAC accepted “promethium”; Giauque won Nobel Prize; Mountain Pass europium deposit discovered
• 1950 – Cerium catalyst use began; Lindsay commercialized neodymium purification; Mountain Pass began europium extraction
• 1950s – Spedding revolutionized rare earth separation; Soviet scandium research continued
• 1951 – Bierman and colleagues demonstrated liver tumor blood supply from hepatic artery; Molycorp began Mountain Pass production
• 1953 – Mountain Pass officially opened; Pure lutetium, ytterbium, and yttrium metals produced
• 1954 – First color CRTs; Spedding demonstrated kilogram-scale rare earth separation
• 1955 – Commercial thulium production established
• 1960 – First laser developed; Yttrium-90 therapy development; Chinese europium process; First pound 99% scandium
• 1960s – Chinese erbium clay deposits discovered, leading to advancements in clay science; Ytterbium steel applications
• 1961 – NIST holmium standards; First Nd laser; Samarium laser built
• 1962 – Holmium ferromagnetism below 19K; Liquid extraction replaces ion exchange
• 1963 – First promethium metal; Mountain Pass major yttrium producer
• 1964 – First Nd:YAG laser; Europium TV phosphors introduced
• 1965 – Scandium alloy patent; Mountain Pass expands; Commercial Nd:YAG production
• 1966 – Strnat discovers samarium-cobalt magnets; YIG filters; Ytterbium-169 uses documented
• 1967 – Color TV broadcasting begins in Europe using PAL format, increasing demand for europium phosphors
• 1969 – Apollo missions returned lunar samples containing yttrium at 54-213 ppm; Russian patent issued for scandium-aluminum alloys
• 1970 – Thulium X-ray devices; Samarium magnets commercialized; Europium NMR reagents
• 1970s – Terfenol-D developed; Lanthanum replaces thorium in glass; Chinese erbium extraction
• 1971 – U.S. Patent 3,619,181 for aluminum scandium alloy granted to Aluminum Company of America; Scientists demonstrate europium chelates’ ability to distinguish between enantiomers
• 1973 – Pure scandium metal produced by electrolysis; Research on rapid rare earth separation by pressurized ion exchange chromatography published; Development of improved europium NMR shift reagents
• 1975 – Small, Stevens and Bauman developed modern ion chromatography; Er:YAG laser operating at room temperature discovered; Cerium dioxide applications expanded in glass manufacturing
• 1976 – Brown demonstrates gadolinium refrigerator; Sm-Nd dating introduced
• 1977 – P.A. Bokhan investigates laser transitions in europium atoms and ions
• 1979 – Gjerde published methods for anion chromatography; Algra and Robertson published ferromagnetic resonance studies on holmium-doped YIG films; Rising cobalt cost spurred neodymium magnet research; Samarium-neodymium dating used to date Rhodesian greenstone belt
• 1980 – Cerium catalytic converters; Cerium glass polishing; Lutetium dating; Europium bulbs
• 1980s – Terfenol-D manufacturing; Chinese erbium techniques; Ytterbium laser materials
• 1981 – H.L. Glass patented temperature-stabilized holmium-containing ferrite films; Masato Sagawa resigned from Fujitsu Laboratories; DePaolo fits quadratic curve to samarium-neodymium isotope data
• 1982 – Dysprosium became key component in neodymium-iron-boron magnets; Technology for manufacturing Terfenol-D developed at Ames Laboratory; General Motors and Sumitomo Special Metals independently discovered Nd2Fe14B compound; Masato Sagawa joined Sumitomo and developed the NdFeB magnet
• 1983 – NdFeB announcements; Reagan’s SDI uses scandium; Yttrium-90 microspheres
• 1984 – Commercial NdFeB production; Terfenol-D developed; Sagawa wins Osaka Prize
• 1985 – Mears demonstrates erbium amplifiers; Holmium magnetocaloric effect; Terbium TV phosphors
• 1986 – Magnequench founded; EDFA demonstrated; Lanthanum superconductor discovered
• 1987 – First commercial EDFA; YBCO superconductor; NiMH batteries with rare earths
• 1988 – First gadolinium MRI agent; Sagawa founds Intermetallics; Yttrium-90 trials
• 1989 – Consumer NiMH cells; Samarium-153 bone therapy
• 1990 – Cerium phosphors and pigments; Dual-stage refrigerator; NiMH popularity; Holmium helifan structure
• 1990s – Wind farms use praseodymium magnets; T-5 lamps; Toyota NiMH batteries; HoLEP developed
• 1991 – Többen demonstrated first erbium-doped fiber laser operating beyond 3 μm; Commercial production of yttrium-90 microspheres began
• 1994 – Holmium laser first used in prostate surgery with Nd:YAG lasers; Three gadolinium-based MRI contrast agents approved in US; Daimler Benz hired IPG Photonics for ytterbium laser development
• 1995 – Holmium laser lithotripsy first reported; EDFA amplifiers deployed in TAT-12/13 submarine cables; Cerium nitrate found effective for burns; GM sold Magnequench to Chinese consortium; De Jong studied [161Tb]Tb-DTPA-octreotide; Mountain Pass closes due to environmental issues and Chinese competition; Scandium alloy patent filed; YAG gemstone production declined
• 1996 – TPC-5CN began operation as first Pacific submarine network using EDFA; IPG Photonics launched industrial 10-watt ytterbium fiber lasers
• 1999 – FDA approved Er:YAG laser for soft tissue surgery; China supplied 99% of global yttrium with 41% of world reserves
• 2000 – Thulium in euro banknotes; Magnequench opens Tianjin plant; IPG introduces 100W ytterbium laser; Yttrium-stabilized zirconia in fuel cells
• 2001 – Prius neodymium version; 50 tonnes thulium oxide/year; 600 tonnes yttrium oxide/year
• 2002 – Research on terbium-doped phosphate fiber published; Development of cubic Ca-ZrO₂ ceramic stains using praseodymium; Giant magnetocaloric effect demonstrated in MnFe(P,As) alloys; IPG Photonics developed multi-kilowatt ytterbium fiber lasers
• 2003 – Dysprosium prices were $7 per pound; North Korea reportedly used Chinese laser weapon containing yttrium; Lanthanum carbonate phase III trials showed effectiveness; Development of NIST’s first ytterbium optical lattice atomic clock began
• 2004 – FDA approved Er:YAG for osseous surgery; World neodymium production ~7,000 tons; Magnequench closes Indiana plant, moves equipment to China; Toyota launches second generation Prius globally; Scandium firearm alloy patent issued
• 2005 – 40W holmium laser systems developed; First documented use of thulium fiber laser for lithotripsy; Sanyo introduced Eneloop NiMH batteries; Camfridge founded as magnetic cooling company
• 2009 – Phase I HEPAR trial began for holmium-166 radioembolization; China’s export restrictions brought attention to dysprosium supply; WHO issued restrictions on high-risk gadolinium contrast agents; NIST’s ytterbium atomic clock achieved precision comparable to cesium fountain clock
• 2010 – Dysprosium critical for clean energy; China restricts exports; Molycorp raises $400M; Global ytterbium 50 tonnes
• 2011 – Dysprosium peaks $1,400/kg; Holmium oxide peak price; ARPA-E funds substitutes; Ytterbium-169 lung therapy
• 2012 – HEPAR 60 Gy dose; Sagawa wins Japan Prize; China produces 50,000 tons magnets; US production restarts
• 2013 – Japan finds Minamitori deposits; APWORKS founded; NIST ytterbium record; China produces 7,000 tons yttrium
• 2014 – Holmium laser superiority; Terbium-155 imaging; Praseodymium in magnets; 6,400 tonnes yttrium production
• 2015 – Molycorp bankruptcy; Australia rare earth industry; APWORKS 3D printing; Ytterbium SI second
• 2016 – 120W holmium lasers; Cerium gene delivery; NIST stable clock; APWORKS motorcycle
• 2017 – IBM holmium bit storage; MP Materials acquires Mountain Pass; FDA gadolinium warnings
• 2018 – LUTATHERA approved for neuroendocrine tumors; Japan publishes Minamitori terbium reserves (420-year supply); Thulium fiber laser commercialized; MP Materials resumes Mountain Pass operations; Premium AEROTEC acquires APWORKS; Northern Minerals opens Australia’s first heavy rare earths mine; Ytterbium-171 clocks achieve 1×10⁻¹⁸ precision
• 2019 – HEPAR PLuS trial; Terbium-161 advantages; FDA approves thulium laser; China 63% global output
• 2020 – COVID impacts markets; Mountain Pass 15.8% global supply; FIA approves Scalmalloy
• 2021 – Boston Scientific $1.07B acquisition; VISION trial; GM announces US facilities; Rio Tinto scandium investment
• 2022 – FDA approves Pluvicto; Sagawa wins Queen Elizabeth Prize; ASP ytterbium facility; US scandium ~45 tonnes/year
• 2023 – FDA fast-tracks lutetium; Lynas dysprosium facility; China 240,000 tons neodymium; Europium market $4.69B
• 2024 – Australia divests Chinese dysprosium stakes; Japan funds Minamitori extraction; China 270,000 tons rare earths; APWORKS Scalmalloy CX
• 2025 – MP Materials opens US refinement facility; Lynas produces dysprosium outside China; APWORKS North American production
• 2026 – NdFeB magnet market projected $19.3 billion

Final Thoughts

The journey of the rare earth elements from scientific curiosities to strategic resources mirrors humanity’s own technological evolution. What began with Johan Gadolin peering at a mysterious black stone in 1794 has culminated in a global industry worth tens of billions of dollars, touching virtually every aspect of modern life. These seventeen elements have proven that true value often lies not in abundance, but in unique properties that enable transformative technologies.

As we stand at the threshold of new technological frontiers—quantum computing, fusion energy, advanced medical treatments—the rare earths will undoubtedly play crucial roles we cannot yet imagine. Their history teaches us that scientific discovery is rarely linear; it’s a story of patient separation, repeated refinement, and sudden breakthroughs that can take centuries to reach their full potential. The gas mantles that lit European streets in the 1890s contained the same cerium that now purifies automotive exhaust and polishes the silicon wafers in our computers.

Perhaps most importantly, the rare earth story reminds us that technological leadership requires more than just innovation—it demands secure supply chains, sustainable extraction methods, and international cooperation. 

As nations scramble to secure their rare earth supplies and reduce dependence on single sources, we’re witnessing a new chapter being written in real-time. The elements that once lay hidden in Swedish rocks now sit at the center of global strategy, proving that in the modern world, the periodic table has become as important as any map in determining the balance of power.

Thanks for reading!

Article Data Sources

1. A History Of Cerium – https://briandcolwell.com/a-history-of-cerium/
2. A History Of Dysprosium – https://briandcolwell.com/a-history-of-dysprosium/
3. A History Of Erbium – https://briandcolwell.com/a-history-of-erbium/
4. A History Of Europium – https://briandcolwell.com/a-history-of-europium/
5. A History Of Gadolinium – https://briandcolwell.com/a-history-of-gadolinium/
6. A History Of Holmium – https://briandcolwell.com/a-history-of-holmium/
7. A History Of Lanthanum – https://briandcolwell.com/a-history-of-lanthanum/
8. A History Of Lutetium – https://briandcolwell.com/a-history-of-lutetium/
9. A History Of Neodymium – https://briandcolwell.com/a-history-of-neodymium/
10. A History Of Praseodymium – https://briandcolwell.com/a-history-of-praseodymium/
11. A History Of Promethium – https://briandcolwell.com/a-history-of-promethium/
12. A History Of Samarium – https://briandcolwell.com/a-history-of-samarium/
13. A History Of Scandium – https://briandcolwell.com/a-history-of-scandium/
14. A History Of Terbium – https://briandcolwell.com/a-history-of-terbium/
15. A History Of Thulium – https://briandcolwell.com/a-history-of-thulium/
16. A History Of Ytterbium – https://briandcolwell.com/a-history-of-ytterbium/
17. A History Of Yttrium – https://briandcolwell.com/a-history-of-yttrium/