Vitrail Lightening Medium is a glossy-finish medium used to create lighter tones without reducing the quality of the color nor making it more fluid. It is a part of the Vitrail Auxiliaries, designed to help artists create special effects with ease when working with Vitrail's ultra-gloss finish paints. These ready-to-use, alkyd oil-based paints allow for subtle shades and added depth on fine art surfaces such as canvas and other non-porous surfaces, and are ideal for both stained glass effects and Mixed Media applications. Either mix Lightening Medium with a Vitrail color before application, use brushes and droppers, or simply drip, spatter and pour the medium directly from the bottle. Available in 45 ml and 250 ml bottles. Conforms to ASTM D-4236.