Unglazed and glazed describe a ceramic surface, not two universal kinds of paint. Before decorating, identify the clay body, its firing stage and whether the finished object will be decorative or used with food and drink.
Three different systems
| Material | What to check |
|---|---|
| Ceramic glaze | Compatible clay body, firing range, application and intended finished use |
| Underglaze | Suitable stage of application and any required covering glaze or firing schedule |
| Air-drying craft paint | The manufacturer’s approved surfaces and decorative-use limits |
Acrylic craft paint on bisque does not become ceramic glaze by drying. Likewise, painting an already glazed mug does not establish that the decorated surface is suitable for food, drink, dishwashing or microwaving.
Follow the complete firing system
AMACO’s clear-glaze guidance distinguishes products and their uses. Use the exact glaze’s label with the clay supplier’s and studio’s firing instructions. Mixing or layering products can change the result; do not transfer a single glaze’s dinnerware claim to an untested combination.
Decorative projects need clear limits
For a display ornament, follow the paint’s surface-preparation and drying instructions and label the result as decorative where necessary. Do not treat a clear craft varnish as proof of food-contact suitability. If you want functional tableware, work with a ceramics studio using a documented compatible clay, glaze and firing process.
Before buying
Confirm access to the required kiln firing before ordering a fired product. Ask the studio whether it accepts that clay and glaze. Buy a small amount for a test tile before coating a finished piece, and evaluate the fired surface rather than the colour in the bottle.
For ordinary non-ceramic craft painting, our acrylic paint guide is a separate route. The two material systems should not share unqualified claims about washing or food safety.