Engraving of hard materials such as stone or glass - involves using bitumen to protect remainder of surface during shot blasting

摘要

A method of engraving hard materials such as stone or glass begins with photographing the required inscription or design on to a silk screen. The design is then transferred to a sheet of fine woven nylon which is placed on the surface to be engraved. The nylon is then covered with a layer of bitumen but the design is left uncovered. The surface is then blasted with abrasive particles which removes material from the unprotected areas whilst the areas protected by the bitumen are untouched. The bitumen is then removed by a suitable solvent.