lines that appear in some iron meteorites when a cross section of the meteorite is etched with weak acid. The pattern is named for Alois Josep Widmanstätten, a Viennese scientist who discovered it in 1808. It represents a section through a three-dimensional octahedral structure in the metal that is formed of bands of kamacite with narrower borders of taenite, the meshes being filled with a mixture of these two alloys. See also Neumann line.