Adding color to etched glass had its beginnings because artists wanted to make more than just etched glass. They wanted the elegance and depth of color. Man has added color to etched stone since the first caveman added color to the scratched figures on the sides of caves. It was only natural that once the art of etching gained popularity, color would come to enhance the work.
Early Egyptians made glass since 1500 B.C., but it wasn't until the 7th century A.D.--when the Germans made forest glass, Waldglas--that it was really well suited for cutting and engraving. By the 1600s, etching techniques used in Bavaria created decorative windowpanes. During the Victorian Era, acid etched glass became more popular on mirrors and windows in England. The end of the glass tax in 1845 made glass cheap enough that shop owners used it for large windows. Pubs, however, had a problem. They didn't want to have their patrons exposed to public view. They added color to the etching to hide the identity of those drinking inside the pubs. Etched and colored glass became extremely popular in England.
The etchings at that time came from beeswax-coated glass. The artists scratched designs in the wax or paraffin and then dipped the glass in hydrofluoric acid to etch, where they created grooves. Because the hydrofluoric acid was so dangerous, many artists lost their lives either slowly through inhalation of the gas from the acid or rapidly if it splashed on their flesh. Creams developed in the 1900s reduced the danger to the artists.
Many paints are available for color glass etching. Some of the paints are opaque and don't allow light to show through; others create more of a stained glass effect where it simply shimmers with color. Glossy paint gives a shiny surface to the etched glass. You also have a selection of various metal-toned paints to use for highlighting your etching. Most people opt for the stained glass paint when they color their glass etching.
The traditional method to apply paint to the etched area is with either a brush, one that came in the paint bottle or a separate artist's brush. The second method of applying paint to your etched glass project is with an airbrush. When artists use an airbrush to add depth and interest to the etched glass, they often use the same process used when they initiated the etching. They create a pattern on paper that leaves only the area they want painted to show. This process uses several light coats for each area colored. Acrylic glass paint is also used. The nice feature of airbrushing etched glass is that the glass, once etched is a great background to allow good adhesion for the paint.
Color adds texture and interest to the etched design, or sometimes is the design. Whether the design is on the flatly etched surface and the etching does nothing more than hold the paint--or, the paint highlights a deeply etched or carved design--it's one method that makes works of art from plain items like a drinking glass or simple slab of glass. Whether paint markers, air brushed or hand painted, the depth and design that color adds to etched glass increases the quality of the design. Occasionally, artists etch the glass and then dip into the paint for a stained glass effect where the opaque etching shows dramatically on the translucent background.