dodecahedra's Usage Examples:

Many other dodecahedra exist as crystal forms, for which see Crystallography.

Magnetite crystallizes in the cubic system, usually in octahedra, less commonly in rhombic dodecahedra, and not infrequently in twins of the " spinel type " (fig.

An important character of blende is the perfect dodecahedral cleavage, there being six directions of cleavage parallel to the faces of the rhombic dodecahedron, and angles between which are 600.

4 illustrates a characteristic twin, formed by two interpenetrating pentagonal dodecahedra.

Lead monoxide is dimorphous, occurring as cubical dodecahedra and as rhombic octahedra.

It crystallizes in the cubic system, usually in cubes, pentagonal dodecahedra or octahedra, often of great beauty and perfection.

Shown above is an icosahedron of twelve dodecahedral structures surrounding a central dodecahedron; (H 2 O) 130.

For this reason the mineral is not always readily recognized by inspection, though the perfect dodecahedral cleavage, the adamantine lustre, and the brown streak are characters which may be relied upon.

The fracture is distinctly crystalline; large crystals, either regular dodecahedra or octahedra, may be obtained by crystallization from carbon bisulphide, sulphur chloride, 'c.

In the " great rhombicosidodecahedron " the dodecahedral faces are decagons, the icosahedral hexagons and the triacontahedral squares; this solid is sometimes called the " truncated icosidodecahedron.

"For this reason the mineral is not always readily recognized by inspection, though the perfect dodecahedral cleavage, the adamantine lustre, and the brown streak are characters which may be relied upon.

It crystallizes in the cubical system, often in beautiful octahedra and rhombic dodecahedra.

The "small stellated dodecahedron," the "great dodecahedron" and the "great stellated dodecahedron" are Kepler-Poinsot solids; and the "truncated" and "snub dodecahedra" are Archimedean solids (see Polyhedron).