Gossamer, glistening translucence is not the look one most commonly associates with polymer clay, but jewelry or buttons made with this simple technique are elegant and sophisticated.

Mokume Gane
A Japanese metalworking technique in polymer clay

by Lindly Haunani

Bead & Button
February 1995

I particularly enjoy jewelry design but used to find the time it took to execute designs in metal very frustrating. So, as an art student, I focused on printmaking.

Everything changed in 1989, however, when I took a polymer clay workshop led by Kathleen Dustin. Polymer clay added a new dimension to my art and enabled me to combine many of my diverse interests - pasta making, food styling, jewelry design, graphic patterning, and the exploration of three-dimensional form, giving free rein to my imagination.

Many techniques from other media are readily adaptable for use with polymer clay, and mokume gane is one of them. Mokume gane is a traditional method of Japanese metalworking that results in a patterning reminiscent of wood grain. It is usually executed in thin sheets of silver, gold, and copper alloys, but achieving proper fusion of the different layers is a difficult challenge. Polymer clay is much easier.

You can achieve beautiful patterning with thin layers of opaque polymer clay. But what I find most exciting is the use of alternating layers of silver leaf and translucent clay (with very small amounts of colored clay mixed in so that the subtle cracking of the silver leaf shows through). The result is a glistening surface pattern with the illusion of depth. When thin slices of of a translucent mokume gane block are applied to a base bead or plaque and rolled in, the overlapping colors appear to blend together.

After making a block of translucent colors in alternating layers with silver leaf, you deform the block and then slice tissue-thin layers off the top of it. For me, the real treasure is these thin slices, which I use to make collages on a base of transparent clay.

Step by Step

1. Mixing and rolling the colors

Since the colors appear to mix where they overlap, I often mix six colors that range through three adjacent colors on the color wheel (for example: blue green, blue, blue violet; blue violet, violet, red violet; yellow green, green, blue green). To obtain maximum translucency, do not use black or white.

Condition the translucent clay by kneading it. Then divide it into six 1-oz. pieces. Mix each portion with one of the '/?-in. halls of colored clay (photo 1). (I do this with my pasta machine.)

As you mix each portion, roll it into a sheet and set it aside on a piece of tracing paper. To do this, I use a pasta rolling machine that I've dedicated to art (photo 2). I set it to the thinnest setting to get an ultra-thin sheet the same size is the silver leaf.

To roll sheets by hand, flatten the clay into a thin round and sandwich it between two sheets of tracing paper or waxed paper. Roll with a rolling pill or braver from the center out, periodically releasing the paper.

2. Layering the block

Open the book of silver leaf (carefully or it will blow away) and press a leaf on top of the first polymer clay sheet (photo 3). Smooth gently. Lay the next clay sheet on top of the silver leaf. Repeat this process with the first five color-blended sheets of clay arranged in the order of your planned color range, pressing gently as you add each layer, then trimming the edges even with the silver leaf. Apply the sixth clay sheet on top of the fifth leaf (photo 4).

3. Contouring the block

Choose which color of the two sides you would like to predominate. Place that side of the block face down on your work surface. Now gently distort the horizontal alignment of the block. To do this and to provide a stable cutting surface, pad the back of the loaf with small strips or lumps of clay. The thickness, shape, and placement of these pieces produces the resulting pattern. Here I've used small halls of clay and pressed them in to anchor them (photo 5).

Turn the block right side up (padded side down). Slowly, working from the center out, press the slab clown to conform to the ridges and valleys (photo 6). Your block should resemble a three-dimensional topographical map of gently rolling hills.

The working consistency of the clay is crucial. If your clay is warm and fairly soft, allow it to rest overnight or longer before going on.

4. Cutting the block

Place the cooled block on a piece of lightweight paper that you can use as a "lazy susan" to rotate the block as you slice it. The blade you use thinnest and sharpest one you have. Tissue slicing blades are available from some bead or craft stores or from the Clay Factory (see mail order sources, p. 21), and this is an excellent excuse to treat yourself to a new blade.

Cut with a sawing motion (imagine you're filleting fish) to remove paper-thin slices from the horizontal face of the block, starting at the top of any hill (photo 7). As you cut the slices, lay them aside on a sheet of tracing paper or waxed paper. To keep cutting evenly across the top of the block, you'll need to rotate it occasionally so that you're cutting from a different edge.

Note: all slices should be the same thinness, but they'll get larger as you shave downward toward the valleys. Remember to keep the blade parallel to the tabletop. If your blade begins to drag, clean it with a lint-free cloth and isopropyl alcohol.

When all the layers have been revealed or the pattern is to your liking, stop cutting (photo 8). The block can be used as is. Or flatten it gently with a brayer or run it through a pasta machine. (Leave the padding pieces on to hold contours when flattening the block.)

5. Collaging the slices

While the block is interesting in itself, I particularly enjoy collaging the ultra-thin slices that I have cut from it. You will gain practice at padding a block to produce a particular pattern, but the slices give you even more design control and versatility. To maximize reflectivity, use translucent polymer clay as the base of your collage.

When making flat pieces, I arrange the slices on a thin sheet of translucent clay. Then sandwich the collage between two layers of tracing paper and smooth it with a roller until all the seams have disappeared (photo 9). Finally, trim the edges even.

If large areas of silver leaf are exposed, I patch over them with a flattened rice-grain-sized piece of translucent clay. And occasionally I make adjustments in the freeform composition by "drawing" on the sheet with thin snakes of tinted clay, made from the trimmings when I sandwiched the block.

Bead shapes are more difficult because the silver leaf tends to crack when it's bent. To alleviate this problem, I apply slices in stages. Roll the bead between your palms in between applications of a few one-slice-thick layers. Then, using a piercing tool or darning needle, make the holes in the beads.

Finish your jewelry by firing according to the manufacturer's directions. After cooling, you may want to buff the pieces with a soft cloth. But never, never use a gloss glaze. It ruins the effect.