Altering and Stamping Rims Kajsa Leijstrom

Appears in the Nov/Dec 2019 issue of Pottery Making Illustrated.

My interest in altering thrown shapes can be traced back to my days as a ceramics student, 25 years ago. Through the years I have developed techniques of pinching, pressing, and pulling with my fingers to transform ordinary wheel-thrown objects into something unique. In more recent years this approach has led to my signature work. The simplicity and efficiency of this way of working is something that appeals to me. I just use my fingers or some very simple tools to do the alterations.

Sometimes, when working with bigger plates and bowls, I go with the flow and make each one unique, but in this case the design repeats because the plates were custom designed to match several big, rounded teacups I had made earlier. I call the design Flower Arch.

Throwing a Plate

The clay I use for this plate and most of my work is a local Swedish stoneware. It’s a very smooth, stable clay body. The amazing dark gray of the raw clay turns into a tan, sand color when fired in oxidation to cone 10. The bare surface is beautiful on its own, but also allows glazes to break nicely over edges and textured decoration.

The process starts on the wheel with throwing a slightly sloped plate with a thicker rim and a nice little throwing spiral line added in the center. I use 1⅓ pounds (600 g) of clay to make this plate 8¾ inches (23 cm) in diameter (1).

The next step can begin when the clay has dried slightly, but is not yet leather hard. Timing this is important: too dry and the clay will crack, too moist and the alterations won’t stay in the desired shape. I wait for an hour or two after throwing, depending on the temperature and humidity in the studio. If thrown in the afternoon, I keep the plates under a plastic sheet overnight and make the alterations the next day.

The Alteration Process

Start the altering process by dividing the plate rim into eight sections with marks to determine the size of the arches. At every mark, press a groove in the rim with your index finger. When altering a plate or bowl, always start from the outside, both because it dries there first and also to define the rhythm and size of the pattern. A simple template can be used to get an even distribution of the sections (2).

Further accentuate the arches by pressing down your index and middle fingers inside the groove you made on the first round. Start this gesture at the rim with a little distance between the fingers, then let them meet as you move toward the center of the plate. A finger on your left hand supports and slightly presses up on the underside of the rim. This will form a pointed, slim, triangular shape, raised from the plate (3).

The arches are extended and given a more rounded shape by pinching the rim between your thumb on the top and index finger underneath. Pull out toward the top center of the arch, alternating from each side of it. Stop pulling before reaching the rim of the plate, to keep the thicker edge. Don’t add any water while completing these steps (4).

A flower decoration is placed in each arch with a stamp that was carved out of a piece of plaster. A bisque-fired, carved clay stamp would also work. Fill out the pattern by holding the stamp firmly against the clay and pressing with your fingers from underneath (5).

Finally, a little twig design is added with a slip trailer. The slip is made from the same clay body as the plate. The lines are drawn pretty quickly to get curves with a good energy, starting from the flower and going toward the tip of the triangle-shaped division between each arch (6).

When the plate has dried to leather hard, turn it upside down and do some trimming. The underside is flat with a mark where the rim begins. There is no defined foot ring.

Once the plates are fired, I dip them into a white tin glaze. The flower decoration and the slip-trailed twig design combine with the features from the throwing and alterations to create raised and recessed textures for the glaze to break over, revealing the dark color of the clay.

Kajsa Leijström is a studio potter in Kivik, Sweden. Learn more about her and her work at www.kajsaskeramik.se and on Instagram @keraleij.