Bisque is Ceramic Clay Greenware Fired One Time

What Is Bisque?

Some of you may be wondering what is ceramic bisque? Bisque is clay that has been fired once. There are all different types of clay such as porcelain, earthenware, and stoneware. There are red clays and white clays. No matter what type of clay you use the process of creating bisque is the same. Bisque starts out in the form of slip which is basically liquefied clay. The slip is poured into a plaster mold which absorbs the water from the clay. As the water is drawn from the clay, the slip begins to form a clay body on the inside of the mold. As more water is absorbed by the plaster mold, the clay body starts to shrink. You should carefully watch the level of the slip and add more slip as needed. When the appropriate thickness is achieved the unused slip is emptied out of the mold. The mold is then turned upside down and continues to drain. After some time the clay begins to pull away from the plaster mold. The clay body is now able to be released from the mold. The newly cast clay body is known as greenware. At this stage the clay is soft and very fragile. After the greenware has dried it is lightly sanded to remove the seam lines from the mold. It is then gently wiped down with a wet sponge to further smooth the greenware. After the piece has been cleaned, the greenware is now ready to be fired for the first time. This is known as the bisque firing which occurs at a cone 04, which is approximately 2000 degrees. The purpose for this firing is to harden the clay to make it ready for decorating. At this stage it is known as bisque.