Potter’s Reduction Diagrams

Potters have been transforming the color and texture of their pottery for thousands of years by exposing their ware to reducing environments during the kiln firing. Through experience, they’ve learned how to achieve the desired level of reduction in their kilns for their clays and glazes. Still, reduction firing results are variable – from shelf to shelf, and firing to firing. Sometimes new colors and interesting textures emerge, but as luck would have it, these happy accidents often end up being difficult to reproduce. The purpose of this article is to introduce a set of Potter’s Reduction Diagrams designed to help potters gain better control over ceramic oxide redox reactions (oxidation-reduction reactions) that affect color and texture in their clays and glazes.