I have made a series of small acrylic paintings (size 30cm x 30cm). The surface on the canvas I have coated with a paste with grains of sand and painted after drying with a dark purple tone. This preparatory work creates a textured surface, which gives the later painting an interesting depth and surface. These textured pastes are available in artist supply stores in a variety of grits.
The two pictures shown can be found in my shop.