Encaustic painting, also called "hot wax painting", involves using heated beeswax to which colored pigments are added. The liquid/paste is then applied to a surface—usually prepared wood, though also canvas and other materials.
Over the intervening centuries, encaustic was overtaken by many other types of paint — including tempera, oil, and acrylic paints — each of which was cheaper, faster, and easier to work.
Encaustic has become so versatile indeed that many contemporary painters consider it an attractive painting medium again.
Once its surface has cooled, encausticpaint presents a permanent finish, and yet the painting can be revised and reworked at any time — whether seconds later or years later.
According to Pliny, encaustic was used in a variety of applications: the painting of portraits and scenes of mythology on panels, the coloring of marble and terra cotta, and work on ivory (probably the tinting of incised lines).
The use of a rudimentary encaustic was therefore an ancient practice by the 5th century B. It is possible that at about that time the crude paint applied with tar brushes to the ships was refined for the art of painting on panels.
Encaustic was a slow, difficult technique, but the paint could be built up in relief, and the wax gave a rich optical effect to the pigment.