Calcined Kaolin (theoretical)
A standard material in Glazecalc's library: its oxide analysis, unity contribution and hazards.
What it is
- Kind
- Clays
- Formula
- Al₂O₃•2SiO₂
- Also called
- Calcined Kaolin, Metakaolin, Calcined China Clay, Roasted Kaolin
- Sold in
- US
- Similar materials
- Glomax LL Calcined Kaolin
- Source
- Theoretical metakaolin Al2O3·2SiO2 (also shown by Digitalfire: Calcined Kaolin)
Kaolin fired to drive off its chemical water, with the same chemistry as kaolin minus the LOI. Recipes listing plain 'calcined kaolin' can use this.
Oxide analysis and unity formula
Glazecalc has the analysis of Calcined Kaolin (theoretical) as weight percent of the raw material. The unity contribution is the moles of each oxide in the amount of Calcined Kaolin (theoretical) that holds 1.0 mole of flux, which is how Glazecalc adds it into a recipe's unity formula.
Calcined Kaolin (theoretical) has no flux oxide, so its unity contribution is per formula as written.
| Oxide | Weight % | Unity contribution |
|---|---|---|
| SiO₂ | 54.1 | 0.900 |
| Al₂O₃ | 45.9 | 0.450 |
- Equivalent weight
- 100
- Fired weight
- 100
- Loss on ignition
- 0%
The equivalent weight is the grams of Calcined Kaolin (theoretical) that hold 1.0 mole of flux. The fired weight is what is left of that after firing.
Hazards and safety
Hazards: Contains crystalline silica (quartz); do not breathe the dust.
Use it in a recipe
Add Calcined Kaolin (theoretical) to a recipe in the Glazecalc calculator to see what it does to a glaze's unity formula.