(Excerpts from ART HARDWARE: The Definitive Guide to Artists’ Materials, by Steven Saitzyk © 1987)
Wax was used as a base for a painting medium since the first century B.C. and remained popular until about A.D. 700. Today, there has been a resurgence in the use of various waxes in painting. These include fossil waxes, paraffin waxes, and beeswax. The use of such waxes in painting is called encaustics, or encaustic painting. The term “encaustic” is derived from the Greek, meaning “burnt in,” which occurs after the painting is completed. This process involves heating the surface to remove all brush or knife marks and to fuse the painting into one solid paint film. Tradition not withstanding, this final burning process is rarely used today. The best surviving examples of early encaustic are the mummy portraits from the Egyptian district of al-Fayyum from the first century B.C. A recent use of encaustic in painting is the Target and Flag paintings by Jasper Johns (c.1955). In these paintings, the pigmented beeswax was applied in translucent layers over strips of newspaper clippings.
The primary advantage of using beeswax, which must be kept warm during application, is that the surface can be worked over as soon as the beeswax pigment mixture cools to room temperature. Since the wax can be softened and dissolved in turpentine or mineral spirits, an encaustic painting can be reworked with a brush and thinner.
Fossil waxes are actually far more commonly used today than the more expensive beeswax. The great advantage to fossil waxes is that they do not require heat to make them pliable. Dorlands Wax Medium is made commercially of fossil wax, which can be mixed directly with oil paint. It is ready to use with or without heat and is relatively inexpensive. It hardens as the solvent evaporates, which takes several times longer than cooling beeswax. Beeswax, despite its great expense, the difficulty of finding it in a pure and bleached state, and its need to be heated, is still preferred for heavy impasto technique.
Wax media set up quickly, drying to the touch within thirty minutes, although final curing is quite slow. A wax-medium paint film will dry with a matte sheen. If desired, a semi-gloss appearance can be created by polishing the heated and cooled surface with a silk cloth. Surface quality has become an important consideration for many contemporary artists, who feel that surface reflection detracts from the direct experience of their work. The major disadvantage in the use of wax is the danger of melting when it is exposed to high temperatures. If you wish to retain the matte quality, remember that this can easily be lost if the surface is polished by improper handling.