Our Impasto & Modeling Wax is a blend of microcrystalline (petroleum) waxes and beeswax. Its purpose is to serve as a build-up material beneath the encaustic paint. It has two advantages over encaustic medium: 1) It is less expensive than encaustic medium, so thickly built-up forms and sculptural work can be done more cheaply. 2) The melting point of the impasto/modeling wax (175' F, 79' C) is a higher temperature than the melting point of encaustic (approximately 162'F, 72' C). The difference in temperature allows one to paint and fuse the encaustic over a shape without immediately blunting sculptural details or impasto effects. The impasto/modeling wax is intended to be used beneath the encaustic. If left exposed, the microcrystalline can, over a period of time, turn yellow due to the effects of atmosphere and ultraviolet light.