This combing technique mimics the colours and pattern of malachite, a mineral containing swirling bands of different greens.

You'll need:
Small brush for base coat
Artist's acrylic paints: black, pthalo green, Hooker's green, white, ultramarine blue
Sand paper, fine
Tack cloth
Low-tack masking tape
Acrylic scumble medium
Brush for glaze
Cotton rags
Combing tool
Brush for varnish
Water-based satin varnish

Here's how:

1. Prepare the surface. Make a combing tool but, for the malachite combing technique, cut the teeth in irregular widths and vary the spacing.

2. Base coat the placemats with two coats of black paint. Sand the surface lightly and wipe away the dust.

3. Use the low-tack tape to mask off a 3cm border around the placemat.

4. Mix the glaze using 1 part pthalo green, 1 part Hooker's green and a touch of white to produce a bright blue-green paint. Mix 1 part blue-green paint, 1 part scumble medium and 1 part water to make the glaze.

5. Apply a coat of the glaze to the base-coated surface. Fold the cotton rag into a wad and gently dab it over the painted surface to break up any brush marks.

6. With the combing tool in one hand and a rag in the other, draw through the glaze using moderate pressure. Wipe the excess paint from the comb onto the rag. The malachite pattern is a series of overlapping swirls and wavering curves - no straight lines. Use the edge of an eraser to create some thicker lines. Allow the glaze to dry and carefully remove the masking tape.

7. Mask off the painted central area and add the blue border.

8. Allow the paint to dry thoroughly. To finish, apply three coats of satin varnish.

Source: Painted Finishes (Murdoch Books)