What was encaustic

Pliny speaks of "painting with wax and burning the paint" (Plin. H.N. 35, 11, 39). Ovid refers to a painting on panel painted with "burned colors" (Ovid. Fasti, 3, 231). Martial, in an epigram on a work depicting Phaeton struck by lightning, says to the painter: "In this panel you have painted Phaeton with encaustic. Do you want then to burn Phaeton a second time?" (Martial, Epigr. 4, 47). Ausonius speaks of the presence of "burned waxes" in the ceilings of the halls (Auson. Epigr. 45, 9). Athanasius the Sinaite defines a painting as a panel with wax colors mixed and burned (Atan. Sina. Sermon on the Sabbath, 7, 4).