refiring

Refiring is the process of firing a ceramic or other material item a second time after an initial firing, typically to finish surfaces, adjust color, or improve properties. In ceramics, refiring often follows an initial bisque firing, after which glaze, underglaze, decals, or slip can be applied and the piece fired again to mature the glaze and bond it to the body. Refiring can also be used to alter glaze appearance, correct defects, or rework pieces that were not fully glazed or uniformly covered.

In practice, refiring requires careful control of temperature, time, and atmosphere to suit both the clay body and the glaze. The second firing is usually chosen to match the glaze’s maturity range and the ceramic’s sensitivity to heat. Potential outcomes include successful vitrification of the glaze, color changes, or improved gloss and durability. However, risks accompany refiring: warping or cracking of the piece, excessive glaze melting, devitrification, pinholing, or glaze crawling. Handling during cooling and avoiding contact with incompatible glazes or decorations are important to prevent damage.

Outside pottery, refiring concepts appear in related crafts such as glass enameling and metal glazing, where surfaces are re-fired to set coatings or achieve new finishes. In industrial contexts, a thorough re-firing may also refer to re-annealing or stress-relief heat treatments of metals.

Overall, refiring is a common technique to enhance appearance and performance but requires compatibility between materials and precise kiln control to avoid defects.