St. John's Black Glaze
The source describes a dark black-blue glaze. Test on tiles first; use ventilation and appropriate PPE, avoid inhaling dust, review raw-material safety data, and verify functional or food-contact suitability with appropriate fired-glaze testing.
- Cone: 9-10
- Atmosphere: oxidation
- Surface: gloss
- Recipe type: glaze
Ingredients
| Material | % |
|---|---|
| Alberta Slip | 65.21739130434783 |
| Nepheline Syenite | 30.434782608695656 |
| Cobalt Carbonate | 4.3478260869565215 |