Underglaze is a versatile ceramic colorant that can be applied to various clay surfaces, but there are certain situations when applying underglaze may not be suitable.
Greenware
Applying underglaze to greenware (unfired clay) can be challenging, as the surface is more fragile and susceptible to damage. It’s often recommended to apply underglaze to leather-hard or bisque-fired clay.
Overglazing
Applying underglaze over a glazed surface may not yield the desired results, as the underglaze may not adhere properly to the glaze. Underglaze is typically applied before glazing and firing.
Unsuitable Firing Temperature
Underglaze is formulated to be fired within a specific temperature range. Applying underglaze to clay that will be fired at a temperature outside of the recommended range may result in unintended outcomes.
Conclusion
While underglaze offers flexibility and creativity in ceramic decoration, it’s important to consider the appropriate timing, surface, and firing conditions for achieving the best results.