| Clay Type | Size (μm × μm) | Specific Surface Area (m2/g) |
| Kaolinite | 1 × 0.1 | 10 - 20 |
| Illite | 0.01 × 0.3 | 90 - 130 |
| Smectite | 0.001 × 0.1 | 750 - 800 |
| Chlorite | 0.01 × 0.3 | 92 - 97 |