
What is Bisque Porcelain?
Bisque porcelain was first made by Chinese crafters. Manufacturing of bisque was done entirely by Chinese for many centuries. Bisque is a white ceramic that is not glazed. Finished pieces are translucent and hard. Most figurines used in decorating are made of this product. Clay used in making bisque porcelain consists of a mixture of flint, kaolin, feldspar. These contents are mixed with water in order to make a paste known as slip. Slip is put into cast and set. Casts absorb the water and the slip quickly hardens around the edges. Within an hour, these edges have become thick enough to allow the remaining liquid to be poured off. This leaves a shell that is porcelain. After thoroughly dry, these porcelain pieces can be removed from casts by gently tapping them.
After removing from casts, pieces are ready to be assembled if needed. Slip is used as an adhesive between pieces. Crafters are careful to conceal seams in their work. Completed pieces are allowed to thoroughly air dry.
When completely dried, pieces are placed in a kiln. Most kilns are heated to around 2,300 degrees F. Depending upon the type of piece, baking times will vary. Some must remain in the kiln for up to 70 hours and others can take as little as 14 hours. During baking in a kiln, pieces will lose all of the moisture. Shrinking will occur as well.