Color variation between production batches is one of the most frustrating quality problems in ceramic manufacturing β tiles from Monday look different from tiles fired on Wednesday, even though nothing in the kiln settings changed.
Color variation between production batches is one of the most frustrating qualit
The most common cause is batch-to-batch variation in raw material chemistry, particularly Fe2O3 content in the flux. If your feldspar supplier delivers material with Fe2O3 ranging from 0.15% to 0.30% between batches (common for poorly controlled dry processors), your fired body color will vary correspondingly
The solution is a supplier with documented batch consistency. Request COA data from 10 consecutive batches and calculate the standard deviation of Fe2O3
See product recommendations below
Understanding This Defect
The most common cause is batch-to-batch variation in raw material chemistry, particularly Fe2O3 content in the flux. If your feldspar supplier delivers material with Fe2O3 ranging from 0.15% to 0.30% between batches (common for poorly controlled dry processors), your fired body color will vary correspondingly. The solution is a supplier with documented batch consistency. Request COA data from 10 consecutive batches and calculate the standard deviation of Fe2O3. At Ceramic Minerals, our wet-process production maintains Fe2O3 variation below plus/minus 0.02% between batches β a level of consistency that eliminates raw-material-driven color variation.
Solution & Prevention
Every shipment includes a COA with independent verification..
Experiencing this defect?
Send us a photo of the defect + your current formulation. Our team provides free troubleshooting support.
