Coarse pumice gel. This lightweight, rough pumice in a fairly fine grind, adds to standard acrylic paint base to produces a sandy surface.
Coarse Pumice gel alone and with acrylic paint added
Photo ©2007 Lesley Shepherd, Licensed to About.com Inc.
Miniaturists find this additive good for crumbling sand effects for railway scenes, as well as pebble dash or rough stucco walls on buildings and dollhouses. This is easiest to use if mixed with the acrylic color you want, then spread with a palate knife or stir stick. It can be brushed on with a very stiff brush, but using a lot of it will destroy the brush.