Pit-fired pottery represents the oldest known method for creating pottery, or firing clay. Different cultures have altered certain methods slightly over time. However, the basics have stayed the same.
The pit-fired pottery process begins by sculpting the clay, either by hand or wheel throwing. The potter then leaves the pieces to dry. Sometimes, terra sigillata (a reddish clay mixture) is added to the greenware (unfired pottery) for color and buffed for a smoother finish. The potter places all of the unfired pots or pieces together in a pit. She then places natural combustibles on top of and around the pots, such as wood chips, manure, saw dust, salt-soaked straw or charcoal. These combustibles are set afire, and metal or larger pieces of wood placed on top.
The fire generally lasts about 2 hours. Pots can be left alone, or removed while still hot for a more recent method called horsehair raku. Using this method, the potter applies and singes horsehair to add decoration. Due to the nature of the way the pots are made, each piece is one of a kind. The way the flames hit the pot and the materials that get burned into and around the pot create distinctive patterns and colors that are impossible to reproduce. Once the pots cool completely, they can be buffed and waxed or have a protective sealant added.
Due to the porous nature of the pots and the fact that they remain unglazed, use pit-fired pottery for decorative purposes only. Don't eat or drink from this type of pottery. If you intend to put water (for flowers, for example) in your pit-fired pottery, add a coat of ceramic sealant to the interior of the pot or it may not hold very well.