The Ceramic Process

How exactly does a plate become a plate? For beginners, this process can seem mystifying and complex, but the basic steps for making a ceramic piece are relatively straightforward. In this lesson, we'll cover this process from start to finish to give you a basic understanding of how that lump of clay becomes a coffee mug.

Forming

There are a wide variety of forming methods, from throwing on the wheel to hand building. You can learn more about them in the lesson: Methods of Making. For the purpose of this lesson, we'll just define this stage of the process as the 'wet stage'. The artist takes a lump of moist clay and shapes it into the desired form, whatever that may be.

Drying

Once the piece is shaped, it must be allowed to dry completely. This process can take anywhere from a few days to a few weeks, depending on the size of the piece and the humidity of the environment in which is is left to dry. All of the water must leave the clay before it can be fired. This is because water turns to gas at 212° F. Water expands during this phase change, so if there is any still trapped in the clay body, it will cause the piece to crack or explode in the kiln.

Bisque Firing

Once the piece is completely dry, it is put into the kiln and fired. This first firing is called the bisque firing. While bisque firing temperatures can vary slightly, the vast majority of artists will bisque at cone 04, which is around 1950° F. During this firing, the clay goes through a structural shift that hardens the clay into a more durable form.

Glazing

Once the piece has been bisqued, it's time to apply the glaze. You can learn more about glazes in the lesson: Glaze 101. The glaze is a layer of glassy material that gives color and finish to the piece, once fired.

Glaze Firing

The second firing is called the glaze firing, and is usually the final step in the ceramic process. Glaze firings vary in temperature depending on the clay and glazes used. During this firing, the glaze matures (goes through a chemical change to become the desired finished product). If a stoneware or porcelain clay is used, the clay also matures during this firing.

Enjoy!

Once they come out of the glaze firing, most pieces are considered 'done', but there are instances where additional firings or finishing treatments might be applied. Gold luster, for example, requires an additional firing after the glaze has been matured. Many potters sand the bottoms of their pieces to smooth them and prevent scratching the table surface. Some artists apply more layers of glaze and re-fire multiple times to build up complex surfaces. Most often, though, this is where the process ends.