A reverse catenary muffle, and method of forming same, includes a planar lower surface, and first and second sidewalls extending upwardly in parallel relation from opposite, first and second edges, respectively, of the lower surface. A concave arch-shaped upper surface extending from upper ends of the first and second sidewalls wherein upper portions of the arch-shaped upper surface are defined at an interconnection of the upper surface with the sidewalls, and a central portion of the upper surface spaced from the lower surface.

A reverse catenary muffle, and method of forming same, includes a planar lower surface, and first and second sidewalls extending upwardly in parallel relation from opposite, first and second edges, respectively, of the lower surface. A concave arch-shaped upper surface extending from upper ends of the first and second sidewalls wherein upper portions of the arch-shaped upper surface are defined at an interconnection of the upper surface with the sidewalls, and a central portion of the upper surface spaced from the lower surface.