Alfred Lacroix

Antoine Francois Alfred Lacroix, known as Alfred Lacroix, was a French mineralogist and geologist born February 4, 1863, in Macon, Saone-et-Loire, France, who died March 12, 1948, and who redefined mineral species concepts by integrating multiple observation methods, conducted extensive studies of volcanic activity on Mount Pelee that clarified the nature of nuees ardentes, or pyroclastic flows, pioneered the classification of eruptive rocks by their conditions of formation, studied contact metamorphism in the Pyrenees, distinguished potassium from sodium-lithium pegmatites in Madagascar, advanced understanding of laterite formation in tropical climates, and applied mineralogical methods to classify stony meteorites. He served as professor of mineralogy at the Jardin des Plantes in Paris from 1893, directed the mineralogical laboratory of the Ecole des Hautes Etudes from 1896, and served as president of the volcanology section of the International Union of Geodesy and Geophysics from 1922 to 1927, publishing La Montagne Pelee et ses eruptions in 1904. He was elected to the Academie des sciences in 1904, was elected a Foreign Member of the Royal Society, received the Hayden Memorial Geological Award in 1923, the Penrose Medal in 1930, and received the Wollaston Medal in 1917.