Noddy Question on Painting and Decorating

Water based pigment does not flow over a surface in the same way that oil based pigments do. For this reason alone it is difficult to soften one pigment colour into another. This being the primary technique of marbling, to create a sense of depth, you can see the problem.

Having stated the above there are many specialist decorators out there creating excellent marble effects using acrylics.

Acrylic pigment, straight out of the tube, will dry a lot quicker than oil colour so we need to slow its drying time down. We do this by adding glycerine. This is the same glycerine used to sooth a sore throat or to make Victoria icing on a cake. Glycerine is the by-product from the splitting of natural oils or fats during Fatty Acid production but basically water with impurities, the impurities stop the water evaporating therefore slowing the drying time.

You can also purchase ready made acrylic scumble which is acrylic varnish with the addition of propylene glycol. Propylene glycol is used in antifreeze, food, plastic and the perfume industries. For all intents and purposes it is a synthetic glycerine.

Experiment by mixing either of the above with acrylic tube colours and blending one colour with another. The colour mix should stay wet until you have achieved your desired effect and at the same time start to dry soon after. You will find the technique a lot quicker than with oil based colours.

When you find, after practice, you can control the blending and softening of colours in water have a look at the sienna marble technique on this site. Although it's referring to oil colours the details are the same.

The beauty of using acrylic colours for marbling is that they do not yellow as do oil colours and there are no solvents used in the process.