Tips and Tools: Clay Gradients Anne Mossman

Appears in the January 2022 issue of Ceramics Monthly.

This method of blending stained clay and plain clay results in a subtle gradation from one color to the other that is even and can be reproduced. 

Creating a Colored Clay

Use any stain you like to make a strong, saturated color, adding at least 5% stain (calculated based on the weight of the clay). I use wet porcelain from the bag. Make a depression in the ball of clay with your thumb. Add the stain to this well along with a few drops of water to dissolve the stain, and mix in thoroughly between your hands (gloves are recommended for direct handling of metallic stains). I always mix in the wet stain initially with a fork, pulling the sides of the clay into the center to cover the stain, preventing it from going all over my hands and therefore being wasted.

Weigh the colored clay you’ve just made and match it with the same weight of uncolored clay from the bag. Roll both pieces out so they are identical in length and thickness (1).

Combining the Clays for Gradients

With the two coils side by side, carefully measure and cut graduated lengths across both pieces (2). In this example I started with a 3mm slice and increased each cut by about 1.5mm (to be 4.5mm long), then 1.6mm (to be 6.1 mm long), then 1.7mm (to be 7.8mm long), etc. 

Working from the end of the colored roll with smaller cuts, pick up the end piece and stick it to the largest section at the opposite end of the white clay roll. Continue placing the colored pieces onto the white pieces until the largest colored piece now has the smallest white piece on top of it (3).  

Each of these pieces now needs to be mixed in turn and placed back down, keeping them in the right sequence (see 4). The clay dries out quickly during this process, so have a damp cotton sheet nearby to place the pieces on and cover them up as you go. 

Laminating Clay

Once the mixing is complete, roll out each piece of blended clay to about 2mm thickness (5). Dampen each disk lightly with a brush of water and lay the next disk on top. Roll and stack each piece in sequence until finished (6). Tip: When laminating clay, always lay the piece down from left to right so that air is not captured between the layers. 

The finished stack should now look like it is going from the lightest shade to the darkest. Cut the stack in half to reveal the graduation (7). The block can now be used by slicing and rearranging as you please.

the author Anne Mossman is based in Australia. Her porcelain vessels are made using the nerikomi method and her latest works reference the iconic eucalyptus. See more on Instagram @annemossman.