Alfred Lacroix (5 December 1863 – 5 July 1948) was a French mineralogist, geochemist, and professor of chemistry and mineralogy. Born in Paris, he studied at the École Normale Supérieure and earned his doctorate in 1889 with a thesis on mineralogical analysis.
Academic career
- Appointed professor of mineralogy at the University of Lyon (1894–1901).
- Served as professor of chemistry and mineralogy at the Collège de France in Paris from 1901 until his retirement in 1935.
Scientific contributions
- Pioneered quantitative chemical analysis of rocks and minerals, advancing the understanding of volcanic processes.
- Conducted extensive field research on the 1902 eruption of Mount Pelée on Martinique, publishing influential reports on the composition and crystallization of pyroclastic materials.
- Authored the multi‑volume textbook Les Minéraux (1905–1912), which became a standard reference for mineralogical classification and crystallography.
- Developed methods for determining trace elements in silicate minerals, influencing subsequent geochemical techniques.
Honors and legacy
- Elected to the French Academy of Sciences in 1918.
- Recipient of the Wollaston Medal of the Geological Society of London (1925).
- The mineral lacroixite (NaAlSO₄·2H₂O) was named in his honor.
Lacroix’s work laid foundational principles for modern petrology and mineral chemistry, and his textbooks continued to be used in higher education well into the mid‑20th century.
