In geometry, the complete, final stellation of the icosahedron, or echidnahedron is the outermost stellation of the icosahedron, and is "complete" and "final" because it includes all of the cells in t

In geometry, the great dodecahedron is one of four Kepler–Poinsot polyhedra. It is composed of 12 pentagonal faces, intersecting each other making a pentagrammic path, with five pentagons meeting at e