Marguerite Perey

Marguerite Catherine Perey (19 October 1909 – 13 May 1975) was a French physicist and a student of Marie Curie. In 1939, Perey discovered the element francium by purifying samples of lanthanum that contained actinium. She graduated from the Sorbonne in 1946 with a Doctorate of Physics; her thesis was about her recently discovered element 87.

Perey earned a chemistry diploma from Paris' Technical School of Women's Education in 1929; while not a "degree", it did qualify her to work as a chemistry technician. In 1929 at the age of 19, Perey interviewed for a role as a personal assistant (technician) to Marie Curie at Curie's Radium Institute in Paris, France, and was hired.

Early career Under Marie Curie's guidance at the Radium Institute, Perey learned how to isolate and purify radioactive elements, focusing on the chemical element actinium (discovered in Curie's laboratory in 1899 by chemist André-Louis Debierne). Perey's discovery was announced by Perrin, not Perey herself, because she was only a laboratory assistant with no university degree. Perey named the element francium, after her home country, and it joined the other alkali metals in Group 1 of the periodic table of elements. Francium is the second rarest element (after astatine) — only about 550g exists in the entire Earth's crust at any given time — and it was the last element to be discovered in nature. She also served as a member of the Atomic Weights Commission from 1950 to 1963.

Perey hoped that francium would help diagnose cancer, but in fact it itself was carcinogenic, and Perey developed bone cancer which eventually killed her. Although a significant step, her election as a "corresponding member" rather than a full member came with limited privileges.

Archives

Perey's archives with materials dating from 1929 to 1975 are housed at the University of Strasbourg. They include laboratory notebooks, course materials from her work as professor of nuclear chemistry, papers from her laboratory directorship, and publications. L’élément 87 Sur les rayonnements β et γ de l'actinium et de l'actinium K "Francium: élément 87," Bulletin de la Société chimique de France, 18: 779 (1951). "Sur la descendance de l'actinium k: 22387Fr," Journal de Physique et le Radium, 17: 545 (1956).