Adding Gall toJacquard Marbling Coloursincreases how much a colour will spread on the marbling size. Add it to the paint to make one colour dominate over the others or to increase the coverage on the marbling surface. Gall can add a whole other dimension to marbling and gives you much more control over the behavior of the paints. Jacquards Synthetic Gall may also be used with other acrylic paints for marbling or increasing flow.