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Defect · Glaze firing
Glaze pitting
Also called: pitting, surface pits
Small depressions or craters in the glaze, often with dark or foreign material visible.
- Appears at
- Glaze firing
- Severity
- Cosmetic
- How common
- Common
Causes
Most likely
- ·Kiln shelf debris falling onto horizontal surfaces
- ·Contaminant particles in glaze or on bisque before firing
Prevention
- ·Keep kiln shelves clean and patched
- ·Sieve glazes before application
- ·Cover glazed ware while stored before firing
Can it be fixed?
- ·Spot-fill pits with glaze and refire for localized repair
Materials involved
Glaze materials whose chemistry sits behind this defect — each links to its reference page.
Related defects
Questions
- Why does glaze pitting happen?
- Most often: Kiln shelf debris falling onto horizontal surfaces. Other causes: Contaminant particles in glaze or on bisque before firing..
- Can glaze pitting be fixed?
- Sometimes. Spot-fill pits with glaze and refire for localized repair.
- How do I prevent glaze pitting?
- Keep kiln shelves clean and patched. Sieve glazes before application. Cover glazed ware while stored before firing.
Sources. Compiled from Claybench's defect reference — the descriptions, causes and remedies that appear consistently across standard ceramics references and studio practice; no single source. It is the same reference the photo diagnosis tool reasons over. Where the Wikibooks Ceramicware Defects Handbook covers a defect it is linked above.
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