Chemical Decoration
Chemical methods of decorating glass use acids to etch designs into glass.
Acid Etching – Acid-etched decoration is created by covering the glass surface with an acid-resistant substance like wax, through which a design is scratched with a sharp object. The glass is then immersed in a hydrofluoric acid bath to etch the exposed areas of glass. The resist was then removed. A patent for acid etching on glass was registered in England in 1857 (All About Glass/Corning Museum of Glass). Acid etching creates a design with a matte or frosted appearance. It was a common decorative technique on lamp globes.
References
n.d. https://allaboutglass.cmog.org/. (This website has an extensive glass dictionary and thousands of photographs).