“Underpainting Lead White (also known as flake white or Cremnitz white) is a mixed white with lead white, titanium white, and chalk ground in oil-alkyd to make a brilliant, opaque white that is smooth, dries very quickly to a matte surface. Not all painters use underpainting, and it seems that those who do want it to dry fast so they can begin coloring in the overpainting. Natural Pigments has a simple solution that does not require buying a whole new set of colors just for the underpainting. Introducing two new products: Underpainting Lead White and Transparent Base. With either or both products, you can use any of your standard oil colors and have them dry blindly fast—usually within an hour or so. Add the Underpainting Lead White or Transparent Base—from one-third to one-half—to your oil color, and your underpainting dries quickly to a matte sheen. Add less for slower drying.” -Natural Pigments