A survey of the crystal structures of materials that are currently being studied in the context of geometric magnetic frustration in triangular lattices is presented, based on a purely geometrical picture of their magnetic lattices. Two-dimensional materials are first described, followed by three dimensional materials of increasing structural complexity. When known, both transition metal and rare earth based examples within a lattice type are noted. The ideal cases are described, as well as the geometries that are found in some materials for which ideal triangular symmetry is broken in different ways. A brief description of materials preparation and crystal growth is also presented.