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Table 2.
XRF semi quantitative analysis of surface hard shell(oxide)%.
| Component | CaO | SiO2 | MgO | Al2O3 | Fe2O3 | K2O |
|---|---|---|---|---|---|---|
| Content% | 45.996 | 12.105 | 3.453 | 1.963 | 0.981 | 0.845 |