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.
Metal tools are used to shape the paint before it cools; also special brushes.
The most renowned use of this medium is in the
Fayum mummy portraits
from Eygpt around A.D. 100-300. See
http://www.encaustic.com/ for more details on the subject.
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