Underglaze colors can undergo changes during firing, and the final color may differ from the appearance of the underglaze before firing.
The temperature at which you fire your piece can affect the color of the underglaze. Higher temperatures may cause the underglaze to darken or intensify in color.
If you apply a clear glaze over the underglaze, the glaze can interact with the underglaze color, potentially altering its appearance.
Opaque vs. Transparent
The opacity of the underglaze can also impact color changes. Opaque underglazes tend to maintain their color better, while transparent underglazes may interact more with the clay and glaze.
Performing test firings with different temperatures and combinations of underglaze and glaze can help you anticipate and control color changes.
Underglaze color changes are a natural part of the firing process, and understanding how different factors influence these changes allows you to achieve the desired color results in your ceramics.