Claude Allegre

Claude Allegre was a French geochemist and politician, born in 1937 and died in 2025, who pioneered the use of mass spectrometry to measure isotope abundances in rocks and minerals with unprecedented precision as a researcher at the Institut de Physique du Globe de Paris. He developed the field of chemical geodynamics, combining isotope geochemistry with geophysical observations to reconstruct how Earth mantle has evolved chemically over billions of years, work recognized with the 1986 Crafoord Prize and the 1995 William Bowie Medal of the American Geophysical Union. He later served as France Minister of Education from 1997 to 2000, a tenure marked by public disputes with the teaching profession.