Luster wax is a synthetic, non-petroleum based wax derived from coal. Small amounts may be added to wax paint to raise the melting point and increase hardness and shine. Requires a 205 F temperature to melt and blend with encaustic paints. Only small amounts should be added and care should be exercised to make sure that the wax paint does not burn. Available in easy-to-melt and dispense prills (tiny granules).