also known as hot wax painting, is a painting technique coming from Antiquity. It uses hot beeswax mixed with colored pigments and other additives such as dammar gum or flaxseed oil.
This liquid paste is then applied to the surface – usually treated wood, possibly cloth, polished paper, or other frequently used materials.
For encaustic painting is nowadays used a specially made small iron. Wax is applied on its surface and then painted on the prepared material.
The Encaustic was used, for example, in funerary portraits in Egypt around 100-300 after Christ, when painting the icon of Blachernitissa and others.
Blachernitissa icon (source: https://commons.wikimedia.org/)