The son of a poor weaver, Haüy received a classical and theological education at the College de Navarre in Paris and was ordained in 1770. His Essai d'une théorie sur la structure des cristaux of 1784 laid the foundation for the mathematical theory of crystal structure. In 1793 he proposed that there were six 'primary forms'-a parallelpiped, rhombic dodecahedron, hexagonal dipyramid, right hexagonal prism, octahedron and tetrahedron. In the Traité de Mineralogie of 1801 these were further divided, which led to the notion of 'molécules intégrantes'. Haüy survived the Revolution and was made Honorary Canon of Notre Dame in 1802.