A pottery glaze is a type of coating applied to the surface of an object, typically ceramic ware. The composition of a glaze determines its color and how it will react to kiln firing. Glazes can also be used for their texture. To see the process in person check out Bennington Potters.
A potter may use the same clay body for an entire production, but then apply different glazes to each individual piece. Pieces that are not going to be glazed would have a shiny, unglazed surface, such as terra cotta.
There are many types of clays that are used to make pottery. The type of clay is determined by the type of clay and the desired result. Alumina is used for making porcelain clay because it helps make the clay white and non-absorbent.
Prepare the bisque
The first step in making a pottery glaze is the bisque stage. Bisque is a type of white clay that can be used on its own or mixed with other types of clays to create a variety of colors in the final product. Bisque can also be used by itself for projects that will not require further painting or decoration after firing. It is typically light in color and is made from pulverized clays, grogs, or feldspars. It is used as a base for any project that will require additional painting or decoration after firing.
Apply the pottery glaze
The second step is to apply the glaze to the pottery surface using either a brush or sponge. A thin layer of glaze is applied with a damp sponge for thin lines or large areas of unglazed pottery, whereas a brush would be used for details such as outlines and decorations. The amount of water in the damp sponge or brush will depend on how thick the layer should be applied.
Fire up the piece
Next in the process is called “firing” and happens at temperatures between 1000°F and 1300°F for about 4 hours. Pottery surfaces are often painted after firing, especially if they have been unglazed in the bisque stage, but there are many different types of finishes that can be applied to both different types and colors of glazes including high gloss, matte, low gloss, and satin finishes.
Why do we glaze ceramics?
The process of glazing ceramic pieces is the final step in the production of pottery. Glazing consists of coating the surface of a piece with a thin, smooth, and usually glossy substance. It is most often done to protect the piece from oxygen and moisture, as well as to create certain colors and textures.