| Clay variety | Silica (SiO2) | Iron oxide (Fe2O3) | Aluminum oxide (Al2O3) | Calcium oxide (CaO) | Potassium oxide (K2O) |
| ABB | 69.84 | ------ | 22.80 | ------ | 7.36 |
| ANT | 66.80 | 10.06 | 20.88 | 2.26 | ----- |
| ARA | 64.76 | 10.58 | 20.57 | ------ | ----- |
| ARG | 62.08 | 10.59 | 20.58 | ------ | 6.76 |
| ARK | 65.00 | 10.08 | 20.86 | 2.38 | 6.76 |
| AVK | 64.38 | 10.00 | 20.37 | ----- | 7.00 |