pH | Total SiO2 % | Al2O3% | Fe2O3% | Feldspar % |
2.0 | 67.62 | 13.80 | 0.140 | 66.24 |
2.0 - 3.0 | 65.91 | 15.30 | 0.120 | 75.86 |
4.0 - 4.5 | 68.46 | 12.80 | 0.145 | 61.44 |