English to Arabic Science Geology Soil

In the case of the HI minerals it is probable that the fixed material is well structured and polycationic which gives the mineral a more stable chemical character.
The same is true for potassium minerals, so called illites.
These minerals can in part be transformed into apparent smectites when submitted to strong bivalent cationic solicitation.
The potassium is replaced by hydrous bivalent cations.
However, not all of the material becomes smectitic in behaviour and some remains in the anhydrous potassium state.
The situation of some layers having a given chemical response to cation selection and others another response gives rise to what is called mixed layering.
In this state some of the 2:1 units in a crystallite have a given cation interlayer occupancy while others have another.