Samarium, a silvery-white metal belonging to the rare earth elements, has journeyed from its obscure discovery in the late 19th century to become an indispensable component in modern technology. This element, named indirectly after a Russian mine official, exemplifies the intricate relationship between scientific discovery, industrial innovation, and technological advancement.

From its initial identification through spectroscopic analysis to its current applications in permanent magnets, nuclear reactors, and medical treatments, samarium’s story reflects broader themes in the history of chemistry and materials science. The evolution of samarium from a scientific curiosity to a strategic material demonstrates how fundamental research can lead to unexpected practical applications that shape our technological landscape.

Reader note: 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 Samarium

This chronological journey reveals how scientific understanding of samarium has progressed alongside developments in analytical techniques, metallurgy, and materials science, ultimately establishing its importance in fields ranging from permanent magnets to cancer treatment.

Chronology

• 1847 – Heinrich Rose describes a new mineral in samples from the Ural Mountains in Russia, later to be named samarskite after Colonel Vassili Samarsky-Bykhovets
• 1853 – Jean Charles Galissard de Marignac observes samarium spectroscopically through sharp absorption lines in an “earth” called didymia
• 1878 – Marc Delafontaine announces a new element decipium but later demonstrates in 1880-1881 that it was a mixture including samarium
• 1879 – Paul-Émile Lecoq de Boisbaudran isolates samarium oxide from the mineral samarskite in Paris and identifies it as a new element via sharp optical absorption lines
• 1885 – William Crookes discovers an unusual orange-colored spectral line in samarium-yttrium mixtures, calling it “anomalous line”
• 1886 – Samarium earth is further separated by Lecoq de Boisbaudran, yielding gadolinium
• 1890 – Paul-Émile Lecoq de Boisbaudran discovers unknown spectral lines in a samarium-gadolinium concentrate
• 1892 – Paul-Émile Lecoq de Boisbaudran discovers three previously unknown blue spectral lines in the spark spectrum of samarium
• 1896 – Eugène-Anatole Demarçay postulates the existence of europium as an impurity in samarium based on ultraviolet spectra
• 1900 – Eugène-Anatole Demarçay confirms that samarium samples contain europium as an impurity
• 1901 – Eugène-Anatole Demarçay produces pure samarium oxide for the first time
• 1903 – Wilhelm Muthmann successfully isolates metallic samarium
• 1950s – Before the advent of ion-exchange separation technology, samarium had no commercial uses in pure form, though “Lindsay Mix” (samarium-gadolinium mixture) was used for nuclear control rods in early nuclear reactors; ion-exchange separation technology becomes available, enabling commercial production of pure samarium
• 1961 – Peter Sorokin and Mirek Stevenson at IBM research labs build one of the first solid-state lasers using samarium-doped calcium fluoride crystals
• 1966 – Karl Strnat at Wright-Patterson Air Force Base discovers samarium-cobalt magnets (SmCo5) with exceptional magnetic properties
• 1970 – Samarium-cobalt magnets are introduced commercially as the first rare earth magnets, revolutionizing permanent magnet technology
• 1972 – Karl Strnat and Alden Ray develop Sm2Co17 magnets with additions of Fe, Cu, and Zr at University of Dayton
• 1970s-1994 – Western militaries rely on a single samarium production plant in La Rochelle, France
• Mid-1970s – Sm-Nd dating technique is introduced to geochemical and cosmochemical communities with advent of modern mass spectrometry
• 1976 – DePaolo and Wasserburg observe that young oceanic volcanics have different neodymium isotope ratios than expected, leading to new understanding of samarium-neodymium geochronology
• Late 1970s – Temperature compensated samarium-cobalt magnets are developed to address specific requirements
• 1979 – Samarium-neodymium dating is used to date Rhodesian greenstone belt volcanics to 2.64 billion years
• 1981 – DePaolo fits a quadratic curve to samarium-neodymium isotope data, representing neodymium isotope evolution
• 1983 – The “positive scram” effect is discovered in samarium-containing control rods at Ignalina Nuclear Power Plant
• 1984 – General Motors and Sumitomo Special Metals independently develop neodymium magnets, which eventually compete with samarium-cobalt magnets
• 1989 – First clinical use of samarium-153 for bone pain palliation is published by Turner et al.
• 1997 – Samarium-153 lexidronam (Quadramet) is FDA approved on March 28 for relief of pain in patients with confirmed osteoblastic metastatic bone lesions
• 2001 – Sartor et al. conduct phase III randomized trial assessing effectiveness of samarium-153 for palliation of bone pain in prostate cancer patients
• 2007 – Samarium-151 is found to be unstable to alpha decay with a half-life of 5×10^18 years
• 2012 – Samarium oxide is cheaper on commercial scale than its relative abundance might suggest due to oversupply
• 2016 – Kagami and Yokoyama develop multi-step chromatographic method for samarium-neodymium dating
• 2017 – FDA updates labeling for Quadramet (samarium-153 lexidronam)
• 2019 – Ashida et al. demonstrate molybdenum-catalyzed ammonia production using samarium diiodide
• 2021 – Sm-promoted layered La2NiO4 perovskite catalysts are developed for hydrogen production via auto-thermal reforming
• 2022 – Recent advances in photocatalytic renewable energy production utilize samarium compounds as catalysts for sustainable hydrogen generation
• 2024 – Boyd and Peters demonstrate samarium(II)-mediated proton-coupled electron transfer for catalytic applications; researchers at Chiba University develop visible-light antenna ligand for samarium catalysis, reducing required amounts to 1-2 mol%

Final Thoughts

The history of samarium illustrates the unpredictable path from scientific discovery to practical application. What began as spectroscopic anomalies in the 1850s has evolved into a critical element for technologies ranging from the world’s strongest permanent magnets to targeted cancer therapies. The development of samarium-cobalt magnets in the 1960s revolutionized electronics miniaturization, while the approval of samarium-153 for medical use opened new frontiers in radiopharmaceuticals.

As we advance further into the 21st century, samarium continues to find new applications in sustainable technologies, particularly in hydrogen production and catalysis. The ongoing research into reducing samarium requirements through innovative techniques like visible-light catalysis suggests that this element’s contributions to science and technology are far from exhausted, promising continued relevance in addressing future technological challenges.

Thanks for reading!

References

[1] Salute to samarium | Nature Chemistry – https://www.nature.com/articles/nchem.2565

[2] WebElements Periodic Table » Samarium » historical information – https://webelements.com/samarium/history.html

[3] Samarium – Wikipedia – https://en.wikipedia.org/wiki/Samarium

[4] Samarium | Rare Earth Element, Uses in Magnets & Alloys | Britannica – https://www.britannica.com/science/samarium

[5] Europium | Elements | RSC Education – https://edu.rsc.org/elements/europium/2020007.article

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

[7] Samarium – https://samplecontents.library.ph/wikipedia/wp/s/Samarium.htm

[8] Samarium–cobalt magnet – Wikipedia – https://en.wikipedia.org/wiki/Samarium–cobalt_magnet

[9] The History of Neodymium Magnets, Part Two | Bunting-Buy Magnets – https://buymagnets.com/the-history-of-neodymium-magnets-part-two/

[10] Magnet Energy / REPM history – Magnetnrg.com – https://www.magnetnrg.com/repm-history.html

[11] Sm–Nd Dating | SpringerLink – https://link.springer.com/content/pdf/10.1007/978-94-007-6326-5_84-1.pdf

[12] Samarium–neodymium dating – Wikipedia – https://en.wikipedia.org/wiki/Samarium%E2%80%93neodymium_dating

[13] Sm–Nd Dating – https://www.researchgate.net/publication/278648801_Sm-Nd_Dating

[14] RBMK – Wikipedia – https://en.wikipedia.org/wiki/RBMK

[15] Lexidronam Samarium Sm 153 – an overview | ScienceDirect Topics – https://www.sciencedirect.com/topics/medicine-and-dentistry/lexidronam-samarium-sm-153

[16] Samarium-153 (Quadramet) | HemOnc.org – A Hematology Oncology Wiki – https://hemonc.org/wiki/Samarium-153_(Quadramet)

[17] QUADRAMET – accessdata.fda.gov – https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/020570s008lbl.pdf

[18] Europium – Wikipedia – https://en.wikipedia.org/wiki/Europium

[19] Rock of ages: Sm-Nd dating with cation-exchange chromatography – 2016 – Wiley Analytical Science – https://analyticalscience.wiley.com/content/article-do/rock-ages-sm-nd-dating-cation-exchange-chromatography

[20] Reductive samarium (electro)catalysis enabled by SmIII-alkoxide protonolysis | Science – https://www.science.org/doi/10.1126/science.adp5777

[21] Samarium-Promoted Layered La2NiO4 Perovskite for Hydrogen Production via the Auto-Thermal Reforming of Acetic Acid – https://www.mdpi.com/1996-1944/18/7/1508

[22] Recent advances in photocatalytic renewable energy production – https://www.oaepublish.com/articles/energymater.2021.24

[23] Revolutionizing Organic Chemistry: The Breakthrough in Samarium-Catalyzed Reactions – Science Emerge – https://scienceemerge.com/revolutionizing-organic-chemistry-the-breakthrough-in-samarium-catalyzed-reactions/