At Bridges 2001, Zongker and Hart  gave a construction for blending two polyhedra using an overlay of dual spherical nets. The resulting blend, they noted, is the Minkowski sum of the original polyhedra. They considered only a restricted class of polyhedra, with all edges tangent to some common sphere. This note defines spherical duals of general convex polyhedra and proves that the Zongker/Hart construction is always valid. It can be used visually, for instance, to morph from any polyhedron to any other.