Marguerite Perey

Discovered the element francium, reshaping the periodic table and nuclear chemistry

Marguerite Perey (1909–1975) was a French physicist and chemist who made a groundbreaking contribution to science by discovering the element francium (atomic number 87) in 1939. Her discovery filled one of the last gaps in the periodic table and provided critical insights into radioactive elements.

Perey began her career as a laboratory assistant to Marie Curie at the Radium Institute in Paris. Despite lacking formal academic credentials initially, her meticulous work ethic and analytical skills led her to identify francium while purifying actinium samples. This achievement earned her a doctorate in 1946, making her the first woman elected to the French Academy of Sciences in 1962.

Her research on francium's properties advanced understanding of alpha decay and nuclear stability. Perey also advocated for safety protocols in handling radioactive materials, influenced by Curie's own health struggles. Though francium's extreme rarity limited practical applications, her work remains a cornerstone of atomic theory.

For more details, visit Atomic Heritage Foundation.