This 1 by 1-inch cube of ablative material was cut from a heat shield that was either tested for or flown as part of a Mercury spacecraft. Built of honeycombed aluminum with many layers of glass-fiber material, the heat shield would boil away as the Mercury capsule descended through the atmosphere. As the silica material (fiberglass) melted, it deposited a white residue on its surface, resembling icing. Without any accompanying provenance, identification of this sample as either a test or flown artifact is impossible.
