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| Oxide | Analysis | Formula | Tolerance |
|---|---|---|---|
| CaO | 0.45% | 0.04 | |
| K2O | 1.20% | 0.06 | |
| MgO | 0.62% | 0.07 | |
| Na2O | 0.30% | 0.02 | |
| Al2O3 | 22.03% | 1.00 | |
| SiO2 | 67.59% | 5.21 | |
| Fe2O3 | 6.62% | 0.19 | |
| LOI | 1.18% | n/a | |
| Oxide Weight | 457.50 | ||
| Formula Weight | 462.96 | ||
Another analysis shows 50% SiO2, 28% Al2O3 and 10% LOI, making it appear kaolinitic (thus likely low in plasticity and refractory). It could also be a red fireclay.
| Typecodes |
Clay Other
Clays that are not kaolins, ball clays or bentonites. For example, stoneware clays are mixtures of all of the above plus quartz, feldspar, mica and other minerals. There are also many clays that have high plasticity like bentonite but are much different mineralogically. |
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