Abstract: A process for the production of homogeneous ream-free bodies made of quartz glass or made of a glass having a high content of silicic acid, in which an essentially bar-shaped initial body is twisted about its longitudinal axis in a shaping step to form a twisted body radially homogenized in layers having axial layering. To make it possible to produce homogeneous large-volume bodies, in at least one further shaping step the twisted body is then softened in a heatable mold under a force acting in the axial direction to deform it in a direction transverse to its axial direction into the mold and form a glass bar, the longitudinal axis of which extends essentially perpendicular to the layering. The glass bar is then twisted about its longitudinal axis.

Abstract: A method of manufacturing a blank for a light-weight mirror. Graphite molding bodies are positioned at regular intervals on a base that functions as a mirror plate or backing plate. The base is surrounded up to the top of the molding bodies with a graphite wall. The interstices between the molding bodies and between the wall and the molding bodies are filled with granular quartz. The assembly is heated in an evacuated furnace to approximately 1730.degree. C. into a honeycomb-shaped supporting structure that is securely fastened to the base. The graphite molding bodies and wall are removed after cooling. Either a backing plate or a mirror plate in the form of another plate is applied to the resulting supporting structure.