Soluble glass can be classified according to:
- type of alkaline cation (sodium, potassium, lithium, quaternary ammonium);
- correlation of mass and moles in glass SiO2 and M2О (where М is sodium, potassium, lithium or quaternary ammonium);
- mass content of impurity oxides Al2O3 , Fe2O3, CaO , MgO, SO3, ;
- density of soluble glass solutions (gr/cm3).
The chemical composition of soluble glass is determined by the content of silicon oxide and other oxides (for example, sodium oxide) independent from its condition in the solution. A silica module is a molecular ratio or mass ratio of silicon oxide to sodium oxide (or to an oxide of any other alkaline cation) multiplied by a coefficient (the coefficient for sodium oxide is 1,0323).