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| Oxide | Analysis | Formula | Tolerance |
|---|---|---|---|
| CaO | 5.98% | 0.43 | |
| K2O | 1.19% | 0.05 | |
| MgO | 3.01% | 0.30 | |
| Na2O | 3.41% | 0.22 | |
| TiO2 | 2.24% | 0.11 | |
| Al2O3 | 13.94% | 0.55 | |
| SiO2 | 54.79% | 3.66 | |
| Fe2O3 | 13.24% | 0.33 | |
| LOI | 2.19% | n/a | |
| Oxide Weight | 392.90 | ||
| Formula Weight | 401.70 | ||
We do not know much about this material, and have lost track of where this analysis is from. However, if this chemistry is correct, this is clearly a well fluxed material that would melt well. It also has an exceptionally high iron content not to mention alot of TiO2.
A potter from Japan told us that the glaze on black Raku tea bowls was made from Kamogawa stone and that they included lead.
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