Atoms, Elements & Molecules, Models Hauy's wooden crystal model and a crystal of alum, c...

Atoms, Elements & Molecules, Models Hauy's wooden crystal model and a crystal of alum, c 1800. Rene-Just Hauy is one of the fathers of the science of crystallography, the study of the molecular structure of crystals and their classification into types. In 1781, he apparently dropped some calcite crystals by accident. He noticed that the broken pieces were rhombohedral in form, and when he deliberately broke other calcite crystals, he discoveredÊ that they all exhibited the same form, regardless of type and source of the sample. He proposed that all the molecules of calcite have the same form, and that they fit together in a regular pattern to form larger structures. Hauy then went on to suggest that similar principles applied to other minerals and that there were sixÊ basic crystal forms on which all mineral structures were based. ©SSPL/Science Museum