(Holohedral ([Greek: holos], whole); Hexakis-octahedral).
Crystals of this class possess the full number of elements of symmetry
already mentioned above for the octahedron and the cube, viz. three
cubic planes of symmetry, six dodecahedral planes, three tetrad axes
of symmetry, four triad axes, six dyad axes, and a centre of symmetry.
[Illustration: FIG. 13.--Rhombic Dodecahedron.]
[Illustration: FIG. 14.--Combination of Rhombic Dodecahedron and
Octahedron.]