Redware is an earthenware clay body with a high iron content. The iron is not evident in the clay when it is workable or when it dries – at those times it is a light gray. But in the heat of the kiln, the clay takes on its characteristic rusty iron color. Since redware clays are widely distributed in natural deposits around the world, it has been the clay most readily available to traditional potters for millennia. It is similar to the type of clay used to make terracotta clay flowerpots and red bricks. We use a redware clay body that is mined and refined in the Berkshire hills of western Massachusetts. The character of this clay body is reminiscent of the clays used by New England redware potters in the 18th and 19th centuries.
After the clay is shaped on the potter’s wheel, it is allowed to dry. Handles, spouts and other additions are attached, and decorative or functional holes or openings are pierced, after the piece sets up to the “leather-hard” stage. The piece must become “bone-dry” before it can be coated with liquid glaze, which we mix to our own specifications. Unlike the 18th-century potters, we make it a point to use no lead or other toxic ingredients in our glazes. Our basic glazes include a clear glaze which allows the clay body’s natural red color to show through; a green glaze created through the use of copper; and two colors of slip, a mustard yellow and a chocolate brown. These colors have been formulated to most closely resemble the colors found on period pieces, while eliminating any toxic ingredients. We also use green, brown and occasionally blue stains to add a dash of color, as the old potters did . (The early potters jokingly referred to the manganese brown stain as “tobacco juice”!)
The pots are then carefully stacked in the kiln and fired to Cone 04 (a temperature of approximately 2,000 degrees Fahrenheit). The kiln must cool down completely before the finished pots can be unloaded. In the interest of economy and energy efficiency, we our pieces in a modern electric kiln.