born Feb. 28, 1743, Saint-Just-en-Chaussée, France
died June 1, 1822, Paris
French mineralogist, one of the founders of the science of crystallography .
He studied theology and was a professor at the Collège de Navarra for 21 years. He became a professor of mineralogy at the Museum of Natural History (1802) and at the Sorbonne (1809). By experimentation he derived a theory of crystal structure, and he subsequently applied his theory to the classification of minerals. He also was known for his studies of pyroelectricity and piezoelectricity in crystals.