In geometry, the small hexagrammic hexecontahedron is a nonconvex isohedral polyhedron.
It is the dual of the small retrosnub icosicosidodecahedron.
It is partially degenerate, having coincident vertices, as its dual has coplanar triangular faces.
Its faces are hexagonal stars with two short and four long edges.
Denoting the golden ratio by
, the stars have five equal angles of
arccos ( ξ ) ≈ 21.031
Each face has four long and two short edges.
The ratio between the edge lengths is The dihedral angle equals
Part of each face is inside the solid, hence is not visible in solid models.
This polyhedron-related article is a stub.