In this paper, we classify and compute the convex foldings of a particular rhombus
that are obtained via a zipper folding along the boundary of the shape. In the
process, we explore computational aspects of this problem; in particular, we outline
several useful techniques for computing both the edge set of the final polyhedron and
its three-dimensional coordinates. We partition the set of possible zipper
starting points into subintervals representing equivalence classes induced by
these edge sets. In addition, we explore nonconvex foldings of this shape
which are obtained by using a zipper starting point outside of the interval
corresponding to a set of edges where the polygon folds to a convex polyhedron;
surprisingly, this results in multiple families of nonconvex and easily computable
polyhedra.