A flexible matt finish, such as Mont Marte Black Gesso, is ideal for priming and sealing canvas, paper, board, and other semi-porous materials. Gesso gives your painting support a slightly toothed surface that makes oil and acrylic stick to it nicely. Use two to three light coats of Black Gesso for optimal effects. Sand between coats to create an extremely smooth surface that is excellent for detailed work and adds intriguing effects and dramatic contrast that regular white gesso cannot. Water can be added to dilute it.