Glass etching is the abrading or roughening of a piece of glass in selected areas in order to produce a design. It is a way to produce a “frosted” design on the surface of a piece of glass, but it is much more than that! It can also be used to carve a design deep into the glass or to produce a shaded design that looks like delicate airbrushing but is permanently etched in the glass. Using the same equipment and techniques, it is also possible to etch or carve on stone, ceramic or wood, and even to etch designs on metal.
There are five types of various techniques are used to achieve an etched surface in glass, whether for artistic effect, or simply to create a translucent surface.
Acid etching is done using hydrofluorosilic acid (H2SiF6) which, when anhydrous, is colorless. The acid is prepared by dissolving silica in a mixture of hydrofluoric acid, quartz powder, calcium fluoride and concentrated sulfuric acid derived after heating.