Encaustic painting uses a medium in which dry pigments are mixed with molten wax (white refined beeswax) and resin. Of the many kinds of wax painting, only that in which the applied colors are burnt in, or fused together by heat, is called "encaustic" (from the Greek for "burning in"). Encaustic paintings can be brilliant in color and can range in texture from smooth transparency to thick impasto. They are also permanent.
Encaustic Painting Technique
Encaustic paints are kept fluid on an electrically warmed palette. The resin gives them hardness and raises their melting temperature. They are applied to a canvas or panel with brushes and palette knives. When a light bulb or therapeutic heat bulb in a reflector is held by hand or fastened near the painting's surface, the brushstrokes flow. When heat is withdrawn, they become sharp and crisp. The painting is then laid flat, and a heat lamp is passed over it at a controlled temperature and distance, burning in the colors to form a homogeneous layer without running or spreading.
The ancient Greeks used encaustic for murals and easel paintings and to color statues. Examples of their work are portraits from Egyptian tombs in Faiyum dating from Roman times. Both Greeks and Romans heated the palette and painting surface with cumbersome containers of glowing charcoal and applied the paint with bronze spatulas or with brushes.
During the Middle Ages, encaustic was replaced by tempera (which is easier to use) and became a lost art. In the 18th and 19th centuries it was revived to paint murals impervious to atmospheric conditions, but it could not withstand water seepage. Since the 1930's, when efficient electrical heating was developed, encaustic has found favor for easel painting.