Pentagonal antiprism

It consists of two pentagons joined to each other by a ring of ten triangles for a total of twelve faces.

If the faces of the pentagonal antiprism are all regular, it is a semiregular polyhedron.

The two pentagonal faces of either shape can be augmented with pyramids to form the icosahedron.

The pentagonal antiprism occurs as a constituent element in some higher-dimensional polytopes.

If these antiprisms are augmented with pentagonal prism pyramids and linked with rings of five tetrahedra each, the 600-cell is obtained.

Three Dimension model of a (uniform) pentagonal antiprism