sandblast, stream of sand or other abrasive particles driven by a jet of compressed air or water or by centrifugal force against a surface to clean or abrade it. When centrifugal force is used, the abrasives are whirled in a rapidly rotating device before being directed against the surface. Powdered quartz, emery, chilled iron globules, and other hard granular substances are used as the abrasive material. The sandblast is used for cleaning castings in foundries; for preparing metal surfaces for painting, enameling, and galvanizing; and for cleaning the stonework of buildings. Frosted designs are worked on glass by placing a stencil or suitable pattern over the surface so that the blast affects only the uncovered parts.