octahedron

the cross section of an octahedron is a square.

八面体的横断面是正方形。

Crystal Habits include the cube, octahedron and pyritohedron (a dodecahedron with pentagonal faces) and crystals with combinations of these forms.

晶体形态常呈立方体、五角十二面体，较少呈八面体，或集合晶簇。