The Process, Continued - Firing & Pitfalls
reduction atmosphere in the kiln around the time that Cone 010 goes down (melts), to ensure that the copper reds come out quickly. If Cone 010 is going down but the atmosphere is still too oxygenated, then I will close off more of the air getting into the kiln, increase the temperature or both.
Things that go Bump in the Night
When you walk into a gallery or store and see a ceramic sculpture or pot you like, you are not only seeing the result of years of hard work by the sculptor or potter to reach that point, but you are seeing a work that survived the limitless ways that a sculpture or pot can be ruined during the creation process.
At almost any stage of the creation of a work, the piece can meet an untimely demise. Here's a brief look at various danger points and the unintended possibilities.
Most potters buy commercially manufactured clay, which may include a number of ingredients in various proportions. Very occasionally, the clay will have the wrong mix of ingredients or the ingredients will be of poor quality. I’ve had pieces of pots blow off in the kiln because the clay was of poor quality.
An impurity in the clay (for example a piece of sponge that gets embedded during throwing) can cause the piece to break during firing. Clays are designed by the manufacturers to reach their full strength at a particular firing temperature. If you fire the clay to a temperature too far below