Encaustic is a beeswax based medium, composed of beeswax, pigment and damar crystals, which is keep molten on a heated palette. The word encaustic comes from the greek word enkaiein, meaning to burn in, referring to the process of fusing paint.
Encaustic is the most beautiful of all paints, it is so versatile. It can be polished to a high gloss, carved, layered, collaged, textured and scraped. It cools immediately, so that there is no drying time, yet it can always be reworked.
Encaustic paintings do not have to be varnished or protected by glass. It is its own protector. This is because beeswax is impervious to moisture, which is one of the major causes of deterioration. Wax resists moisture far more than varnish or oil. Buffing encaustic will give luster and saturation to color in just the same way that varnish does. credit , R&F Paints