Terbium, a silvery-white rare earth metal belonging to the lanthanide series, stands as one of the most technologically significant elements despite its relative scarcity in the Earth’s crust. Named after the Swedish village of Ytterby, where its ore was first discovered, terbium has evolved from a scientific curiosity in the 19th century to an indispensable component in modern technology. This remarkable element, with atomic number 65, exhibits unique magnetic and luminescent properties that have revolutionized fields ranging from color television displays to advanced magnetostrictive materials. Today, terbium plays a crucial role in green phosphors, solid-state devices, wind turbine magnets, and cutting-edge medical applications, making it an essential material for the 21st century’s technological infrastructure.

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. The complete history of all 17 rare earth elements can be found here.

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

A History Of Terbium

The history of terbium spans nearly two centuries, from its discovery in 1843 by Swedish chemist Carl Gustaf Mosander to its current status as a critical material for modern technology. This chronology traces terbium’s journey from a barely distinguishable impurity in yttrium oxide to an essential component in green phosphors, magnetostrictive alloys, and advanced medical applications, highlighting the element’s increasing importance in fields ranging from consumer electronics to renewable energy and national defense.

Chronology

• 1843: Carl Gustaf Mosander discovered terbium as an impurity in yttrium oxide (Y2O3) while studying the mineral gadolinite from the Ytterby mine in Sweden. Mosander separated yttria into three fractions using ammonium hydroxide, naming them yttria, erbia, and terbia. He presented his discovery at the 13th meeting of the British Association for the Advancement of Science held at Cork, Ireland, August 17-23, in a paper titled “On the new metals, Lanthanium and Didymium, which are associated with Cerium; and on Erbium and Terbium, new metals associated with Yttria.” The discovery was initially contested by spectroscopist Nils Johan Berlin. [1, 2, 3, 4, 5]
• 1864: Marc Delafontaine used optical spectroscopy to prove that yttrium, terbium, and erbium were indeed separate elements, confirming Mosander’s discovery. [6]
• 1877: Scientists reversed the names of erbia and terbia due to confusion caused by similarities between their properties and names. What Mosander called erbia became terbia and vice versa. [7, 8]
• 1881: Researchers noted there was no satisfactory method to separate erbia from terbia, highlighting the difficulty in isolating terbium from its neighbor elements. [9]
• 1886: Jean-Charles-Galissard de Marignac, a French chemist, first prepared terbium in pure form. [10]
• 1898: William Crookes misidentified an alloy of gadolinium and terbium as a new chemical element called “victorium” based on its unique phosphorescence and ultraviolet-visible spectral phenomena. [11]
• 1905: Georges Urbain proved that “victorium” was false and actually an impurity of gadolinium and terbium, not a new element. Urbain established that there were fifteen rare earth metals, including terbium, through thousands of fractional crystallizations. Pure terbium compounds were first prepared. [12, 13, 14, 15, 16]
• 1906: G. Eberhard published “A Spectroscopic Investigation of Dr. Urbain’s Preparations of Terbium” in Astrophysical Journal, documenting spectroscopic properties of pure terbium. [17]
• 1914: The process of separating terbium from gadolinium and dysprosium was described as “tedious” but possible, using different solvents. [18]
• 1932: Mary Elvira Weeks published “The discovery of the elements. XVI. The rare earth elements” in Journal of Chemical Education, documenting the history of terbium’s discovery. [19]
• 1937: Werner Fischer and colleagues developed the liquid-liquid extraction process that would become the basis for modern terbium extraction methods. [20]
• 1940: Georges Champetier and Charlotte H. Boatner published a biographical article on Georges Urbain, who had confirmed terbium’s identity as a distinct element. [21]
• 1947: Frank Spedding and colleagues at Ames Laboratory published the first of a series of papers describing practical methods for preparative separation of rare earths including terbium by displacement ion-exchange chromatography. The Ames Laboratory was formally established this year under Spedding’s direction. [22, 23, 24]
• 1947: The Separation of Rare Earths by Ion Exchange studies were published, demonstrating ion exchange methods for separating terbium from other rare earth elements. [25, 26, 27]
• 1954: Spedding’s Ames group demonstrated their ability to separate kilograms of high-purity (>99.99 percent) individual rare-earth elements including terbium using ion exchange methods. This marked the practical implementation of industrial-scale rare earth separation. [22, 28, 24]
• 1954: RCA produced some of the first color CRTs. Though not yet using terbium-based phosphors, this marked the beginning of color television technology. [29, 30]
• 1958: W. C. Thoburn, S. Legvold, and F. H. Spedding published “Magnetic Properties of Terbium Metal” in Physical Review, documenting terbium’s magnetic characteristics. [31]
• 1962: Liquid-liquid extraction methods began to replace ion exchange methods for industrial-scale separation of rare earth elements including terbium, as it was inherently simpler and more efficient. The technology was rapidly adopted globally concurrent with growing need for terbium in television phosphors and permanent magnets. [22, 32]
• 1964: The first red emitting rare-earth phosphor, YVO4:Eu3+, was introduced by Levine and Palilla as a primary color in television, beginning the era of rare earth phosphors in color TV. [33]
• 1965: Brighter rare earth phosphors, including terbium-activated phosphors, began replacing dimmer and cadmium-containing red and green phosphors in cathode ray tubes. [34, 30]
• 1972: Rare earth phosphors for X-ray intensifying screens were introduced, including terbium-activated gadolinium oxysulfide. Buchanan et al. published research showing terbium-activated lanthanum oxysulfide screens were 4-6 times more efficient than calcium tungstate screens. [35, 36, 37, 38]
• 1973: Research on rapid rare earth separation by pressurized ion exchange chromatography was published, improving terbium separation efficiency. [39]
• 1974: Terfenol-D (TbxDy1−xFe2), a magnetostrictive alloy containing terbium, iron, and dysprosium, development continued at the Naval Ordnance Laboratory in the United States for high-power sonar applications. The name Terfenol originated from Terbium (TER), Iron (FE), and Naval Ordnance Laboratory (NOL). [40, 41, 42, 43]
• 1982: The technology for manufacturing Terfenol-D efficiently was developed at Ames Laboratory under a U.S. Navy-funded program, enabling practical production of the magnetostrictive material. [44, 45, 46]
• 1983: A patent for a green luminescent cathode-ray tube device using terbium-activated phosphor was filed, addressing suppression of undesired radiations at 490 nm, 586 nm, and 620 nm. [47]
• 1984: Iowa State University’s Ames Laboratory, the U.S. Department of Energy, and the U.S. Navy Surface Weapons Research Center jointly developed terbium dysprosium iron giant magnetostrictive material. [48]
• 1985: Terbium-containing green phosphors became standard in color television cathode ray tubes, combined with europium phosphors for trichromatic lighting technology. [49]
• 1990: Geoffrey Green and coworkers used terbium with gadolinium to build a dual-stage room-temperature magnetic refrigerator prototype, with gadolinium as a high-temperature stage and terbium as a low-temperature stage. [50]
• 1992: Terbium began seeing significant use in fiber optic applications and magneto-optical devices. Research on terbium-doped optical fibers for telecommunications and optical isolators expanded. Dense wavelength division multiplexing (DWDM) technology increased capacity of fiber optic networks. [51, 52, 53]
• 1995: De Jong et al. conducted the first preclinical study involving [161Tb]Tb-DTPA-octreotide, finding promising results for targeted radionuclide therapy. [54]
• 1998: First commercial application of Terfenol-D in the SoundBug device by FeONIC, demonstrating practical magnetostrictive applications. [55]
• 2001: James L. Marshall and Virginia R. Marshall published “Rediscovery of the Elements: Ytterby Gruva (Ytterby Mine)” documenting the historical site where terbium-containing minerals were first discovered. [56]
• 2002: Research on effective Verdet constant in terbium-doped-core phosphate fiber was published, advancing magneto-optical applications. [51]
• 2004: Per Enghag published “Encyclopedia of the elements: technical data, history, processing, applications,” providing comprehensive information about terbium’s properties and applications. [57]
• 2009: L. Sun and colleagues published research on effective Verdet constant in terbium-doped-core phosphate fiber for magneto-optical applications. [51]
• 2010: Quantitative SPECT imaging research for terbium-155 and terbium-161 began advancing for preclinical theranostic radiopharmaceutical development. [58]
• 2011: Research on terbium compounds for targeted alpha therapy and medical imaging applications intensified. [54]
• 2012: Müller et al. published a proof-of-concept study demonstrating all four terbium radioisotopes (149Tb, 152Tb, 155Tb, 161Tb) for PET, SPECT, and radiotheragnostic applications using a DOTA-folate conjugate. [59, 60, 61]
• 2013: Japan Agency for Marine-Earth Science and Technology discovered rare earth element deposits, including terbium, in deep-sea mud near Minamitori Island (Marcus Island), about 250 km south of the island at depths of 5,600 to 5,800 meters. [62, 63]
• 2014: Clinical evaluation studies of terbium-155 for SPECT imaging showed advantages over indium-111, with Müller et al. demonstrating superior imaging characteristics. [54, 64]
• 2015: Multiple research groups advanced terbium-161 development for targeted radionuclide therapy, showing superior antitumor effects compared to lutetium-177 due to co-emission of Auger electrons. [54]
• 2016: Research on magneto-optical properties of terbium-lutetium–aluminum garnet crystals showed high thermal conductivity and transmittance for high-power laser systems. [65]
• 2017: Baum et al. conducted the first-in-human PET/CT study with 152Tb-DOTATOC, marking terbium-152 as the first terbium isotope tested in a patient. [66, 60]
• 2018: Japanese researchers published in Scientific Reports that the Minamitori Island deposit contains enough terbium to meet global demand for 420 years, describing it as having the potential to supply these materials on a semi-infinite basis to the world. [67, 68, 69]
• 2019: Research groups demonstrated the therapeutic potential of terbium-161 for PSMA-targeted radionuclide therapy of prostate cancer, showing advantages over lutetium-177. [54]
• 2020: The annual global demand for terbium was estimated at 340 tonnes (750,000 lb), highlighting its importance in modern technology applications. Paramagnetic borotungstate glasses with high terbium concentration were developed for magneto-optical applications. [70, 71]
• 2021: Comprehensive reviews on terbium radionuclides for theranostic applications were published, covering production challenges and clinical potential. First-in-human application of terbium-161 using 161Tb-DOTATOC demonstrated feasibility. [54, 64, 72]
• 2022: Research on terbium-161 combination with somatostatin receptor antagonists suggested a potential paradigm shift for treating neuroendocrine neoplasms. Cyclotron production methods for terbium-155 were optimized for SPECT imaging. [54, 64]
• 2023: Studies on tetravalent terbium complexes advanced understanding of high-valent lanthanide chemistry, with applications in catalysis and materials science. Research on quantitative SPECT imaging of terbium-155 and terbium-161 advanced preclinical development. [73, 58]
• 2024: Japan approved allocation of 44 million USD to develop technologies for extracting terbium and other rare earth elements from deep-sea muds near Minamitori Island. Comprehensive reviews on terbium radionuclides for theranostic applications in nuclear medicine were published. [74, 75]
• 2025: Terbium continues to be essential for green phosphors in displays, Terfenol-D magnetostrictive devices, wind turbine magnets, and medical applications including targeted alpha therapy using terbium-149. [76, 77]

Final Thoughts

As we look toward the future, terbium’s story exemplifies how a seemingly obscure scientific discovery can become fundamental to technological progress. From Carl Gustaf Mosander’s patient separation work in 1843 to today’s deep-sea mining initiatives near Japan’s Minamitori Island, terbium has transformed from a chemical curiosity to a strategic resource. Its unique properties – particularly its brilliant green fluorescence and exceptional magnetostrictive behavior – have made it irreplaceable in applications ranging from smartphone screens to naval sonar systems. The recent discovery of vast terbium deposits in Pacific Ocean sediments promises to reshape global supply chains and reduce dependence on traditional sources.

As humanity advances toward more sustainable technologies, including wind turbines and energy-efficient lighting, terbium’s role will only grow more critical. The element that once confused scientists with its similar-named sibling erbium now illuminates our screens, powers our clean energy infrastructure, and may soon revolutionize medical treatments through radioactive isotopes. Terbium’s journey reminds us that today’s laboratory curiosity may become tomorrow’s indispensable technology.

Thanks for reading!

References

[1] Terbium – Wikipedia – https://en.wikipedia.org/wiki/Terbium

[2] Terbium – https://www.chemicool.com/elements/terbium.html

[3] Terbium (Tb) – Discovery, Occurrence, Production, Properties and Applications of Terbium – https://www.azom.com/article.aspx?ArticleID=7961

[4] Carl Gustaf Mosander and His Research on Rare Earths | SpringerLink – https://link.springer.com/chapter/10.1007/978-94-009-0287-9_3

[5] Carl Gustaf Mosander – Wikipedia – https://en.wikipedia.org/wiki/Carl_Gustaf_Mosander

[6] Learn Carl Gustaf Mosander facts for kids – https://kids.kiddle.co/Carl_Gustaf_Mosander

[7] It’s Elemental – The Element Terbium – https://education.jlab.org/itselemental/ele065.html

[8] Terbium Facts, Symbol, Discovery, Property, Uses – https://www.chemistrylearner.com/terbium.html

[9] Terbium | Rare Earth Element, Atomic Number 65 | Britannica – https://www.britannica.com/science/terbium

[10] Terbium compounds – Wikipedia – https://en.wikipedia.org/wiki/Terbium_compounds

[11] Erbium – https://www.chemicool.com/elements/erbium.html

[12] Carl Gustaf Mosander | Discovery of Lanthanides, Cerium & Didymium | Britannica – https://www.britannica.com/biography/Carl-Gustaf-Mosander

[13] Terbium summary | Britannica – https://www.britannica.com/summary/terbium

[14] Carl Gustav Mosander – Oxford Reference – https://www.oxfordreference.com/display/10.1093/oi/authority.20110803100211520

[15] Carl Gustaf Mosander | Elements Wiki | Fandom – https://periodictableofelements.fandom.com/wiki/Carl_Gustaf_Mosander

[16] Cathode-ray tube – Wikipedia – https://en.wikipedia.org/wiki/Cathode-ray_tube

[17] A Spectroscopic Investigation of Dr. Urbain’s Preparations of Terbium – Astrophysical Journal

[18] Separation of Terbium from Gadolinium and Dysprosium – Journal of Chemical Education

[19] The discovery of the elements. XVI. The rare earth elements – Journal of Chemical Education

[20] Liquid-liquid extraction process for rare earth separation – Industrial Chemistry Journal

[21] Georges Urbain biographical article – Journal of Chemical History

[22] Frank Spedding – Wikipedia – https://en.wikipedia.org/wiki/Frank_Spedding

[23] Frank Spedding – Nuclear Museum – https://ahf.nuclearmuseum.org/ahf/profile/frank-spedding/

[24] Early milestones in the development of ion-exchange chromatography: a personal account – ScienceDirect – https://www.sciencedirect.com/science/article/abs/pii/S0021967304000202

[25] The Separation of Rare Earths by Ion Exchange.1,2 I. Cerium and Yttrium | Journal of the American Chemical Society – https://pubs.acs.org/doi/10.1021/ja01203a058

[26] The Separation of Rare Earths by Ion Exchange.1,2 II. Neodymium and Praseodymium | Journal of the American Chemical Society – https://pubs.acs.org/doi/10.1021/ja01203a060

[27] The Separation of Rare Earths by Ion Exchange.1 III. Pilot Plant Scale Separations | Journal of the American Chemical Society – https://pubs.acs.org/doi/10.1021/ja01203a063

[28] Separation of Rare Earth Elements – American Chemical Society – https://www.acs.org/education/whatischemistry/landmarks/earthelements.html

[29] History of television – Wikipedia – https://en.wikipedia.org/wiki/History_of_television

[30] Color Television – an overview | ScienceDirect Topics – https://www.sciencedirect.com/topics/earth-and-planetary-sciences/color-television

[31] Magnetic Properties of Terbium Metal – Physical Review

[32] Processing the ores of rare-earth elements | MRS Bulletin – https://link.springer.com/article/10.1557/s43577-022-00288-4

[33] Red emitting rare-earth phosphor YVO4:Eu3+ – Levine and Palilla

[34] Television set – Wikipedia – https://en.wikipedia.org/wiki/Television_set

[35] US4507560A – Terbium-activated gadolinium oxysulfide X-ray phosphor – Google Patents – https://patents.google.com/patent/US4507560A/en

[36] US3974389A – Terbium-activated rare earth oxysulfide X-ray phosphors – Google Patents – https://patents.google.com/patent/US3974389A/en

[37] Terbium-activated lanthanum oxysulfide screens – Buchanan et al.

[38] X-ray intensifying screens with rare earth phosphors – Medical Physics Journal

[39] Rapid rare earth separation by pressurized ion exchange chromatography – ScienceDirect – https://www.sciencedirect.com/science/article/abs/pii/0022190273800855

[40] Terfenol-D – Wikipedia – https://en.wikipedia.org/wiki/Terfenol-D

[41] Top 20 Terfenol-D companies – Discovery|PatSnap – https://discovery-patsnap-com.libproxy1.nus.edu.sg/topic/terfenol-d/

[42] Terfenol-D | Military Wiki | Fandom – https://military-history.fandom.com/wiki/Terfenol-D

[43] Naval Ordnance Laboratory development of magnetostrictive materials

[44] News – Magical Rare Earth Element: Terbium – https://www.epomaterial.com/news/magical-rare-earth-element-terbium/

[45] Terbium compounds – Wikipedia – https://en.wikipedia.org/wiki/Terbium_compounds

[46] TdVib, LLC Terfenol-D – ETREMA Products, Inc. – http://tdvib.com/terfenol-d/

[47] Green luminescent cathode-ray tube device with improved color filtering system – North American Philips Corporation – https://www.freepatentsonline.com/4538089.html

[48] Giant magnetostrictive material development – Iowa State University

[49] Phosphor – Wikipedia – https://en.wikipedia.org/wiki/Phosphor

[50] Dual-stage magnetic refrigerator prototype – Geoffrey Green et al.

[51] Fiber structures and material science in optical fiber magnetic field sensors | Frontiers of Optoelectronics – https://link.springer.com/article/10.1007/s12200-022-00037-0

[52] rare-earth-doped fibers – erbium, ytterbium, thulium, praseodymium, codoping, lasers, amplifiers, active fibers, double-clad, amplifier fibers – https://www.rp-photonics.com/rare_earth_doped_fibers.html

[53] The History and Importance of Fiber Optic Technology – Flytec Computers – https://flyteccomputers.com/blog/the-history-and-importance-of-fiber-optic-technology/

[54] Terbium radionuclides for theranostic applications in nuclear medicine: from atom to bedside – PMC – https://pmc.ncbi.nlm.nih.gov/articles/PMC10879862/

[55] SoundBug device by FeONIC – First commercial Terfenol-D application

[56] Rediscovery of the Elements: Ytterby Gruva (Ytterby Mine) – James L. Marshall and Virginia R. Marshall

[57] Encyclopedia of the elements: technical data, history, processing, applications – Per Enghag

[58] Quantitative SPECT imaging of 155Tb and 161Tb for preclinical theranostic radiopharmaceutical development | EJNMMI Physics | Full Text – https://ejnmmiphys.springeropen.com/articles/10.1186/s40658-024-00682-8

[59] A unique matched quadruplet of terbium radioisotopes for PET and SPECT and for α- and β- radionuclide therapy: an in vivo proof-of-concept study with a new receptor-targeted folate derivative – https://pubmed.ncbi.nlm.nih.gov/22996348/

[60] Scandium and terbium radionuclides for radiotheranostics: current state of development towards clinical application – PMC – https://pmc.ncbi.nlm.nih.gov/articles/PMC6475947/

[61] Terbium Radionuclides for Theranostic Applications in Nuclear Medicine – https://openmedscience.com/terbium-radionuclides-for-theranostic-applications-in-nuclear-medicine/

[62] Minamitorishima – Wikipedia – https://en.wikipedia.org/wiki/Minamitorishima

[63] Japan’s massive rare earth discovery threatens China’s supremacy – MINING.COM – https://www.mining.com/japans-massive-rare-earth-discovery-threatens-chinas-supremacy-89013/

[64] Cyclotron production and radiochemical purification of terbium-155 for SPECT imaging | EJNMMI Radiopharmacy and Chemistry | Full Text – https://ejnmmipharmchem.springeropen.com/articles/10.1186/s41181-021-00153-w

[65] Magneto-optical property of terbium-lutetium-aluminum garnet crystals – ScienceDirect – https://www.sciencedirect.com/science/article/abs/pii/S0925346717300836

[66] First-in-human PET/CT with 152Tb-DOTATOC – Baum et al.

[67] How the mud near this small Japanese island could change the global economy | CNN – https://www.cnn.com/2018/04/16/asia/japan-rare-earth-metals-find-china-economy-trnd/index.html

[68] Japan Discovered a Rare-Earth Mineral Deposit That Can Supply The World For Centuries : ScienceAlert – https://www.sciencealert.com/japan-discovered-a-rare-earth-mineral-deposit-that-can-supply-the-world-for-centuries

[69] Japanese researchers discover new supply of rare earths – https://cen.acs.org/materials/Japanese-researchers-discover-new-supply/96/i17

[70] Annual global demand for terbium – Industry Report 2020

[71] Terbium concentration effect on magneto-optical properties of ternary phosphate glass – ScienceDirect – https://www.sciencedirect.com/science/article/abs/pii/S0925346720300434

[72] Frontiers | Theranostic Terbium Radioisotopes: Challenges in Production for Clinical Application – https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.675014/full

[73] Design, Isolation, and Spectroscopic Analysis of a Tetravalent Terbium Complex | Journal of the American Chemical Society – https://pubs.acs.org/doi/abs/10.1021/jacs.9b06622

[74] Japan eyes production from REE-rich muds – GeoExpro – https://geoexpro.com/japan-eyes-production-from-ree-rich-muds/

[75] Comprehensive reviews on terbium radionuclides for nuclear medicine – 2024

[76] Current applications of terbium in technology – 2025

[77] Rare-earth element – Wikipedia – https://en.wikipedia.org/wiki/Rare-earth_element