The revolutionary oil-based core creates a rich vibrant colour that is resistant to prolonged colour change ensuring artwork will not fade for up to 100 years under museum conditions. Colours can be mixed on the page to create a paint-like effect and features a strong point for detailed drawing and layering techniques, and has a selection of rich colour selection with quick and opaque colour laydown. Comply with ASTM D6902 and Blue Wool Scale ISO 105.