Engraving is a process of decorating cold glass by removing material. There are several modes of engraving: direct engraving, with the wheel and the point or indirect, with the acid and the jet of sand. Sandblasting consists of projecting sand through a nozzle under compressed air pressure to attack the glass more or less deeply. The decoration is frosted by this projection while the parts to be spared are protected by a stencil.
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