Adding Gall to Jacquard Marbling Colors increases how much a color will spread on the marbling size. Add it to the paint to make one color 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. Jacquard’s Synthetic Gall may also be used with other acrylic paints for marbling or increasing flow.