In geometry, the tridyakis icosahedron is the dual polyhedron of the nonconvex uniform polyhedron, icositruncated dodecadodecahedron. It has 44 vertices, 180 edges, and 120 scalene triangular faces. Proportions The triangles have one angle of , one of and one of . The dihedral angle equals . Part of each triangle lies within the solid, hence is invisible in solid models. See also Catalan solid Duals to convex uniform polyhedra Uniform polyhedra List of uniform polyhedra References Photo on page 96, Dorman Luke construction and stellation pattern on page 97. Dual uniform polyhedra