From Online Dictionary of Crystallography
Revision as of 13:17, 16 November 2017 by BrianMcMahon (Added German translation (U. Mueller))
Ogdoédrie (Fr). Ogdoedrie (Ge). Ogdoedria (It). 八面像(Ja). Ogdoedría (Sp).
The point group of a crystal is called ogdohedry if it is a subgroup of index 8 of the point group of its lattice.
In three-dimensional space there is only one ogdohedry: it corresponds to the geometric crystal class 3 of crystals belonging to the hexagonal lattice system (in the case of rhombohedral crystals, it corresponds instead to a tetartohedry).