In this study two routes for the gelation of water glass have been investigated; the destabilization by a
change in pH and by an increase in concentration through evaporation. Both methods produce optically
transparent, highly viscous, homogeneous solutions. The structure and dynamics of the solutions along
the two routes have been investigated with dynamic light scattering, 29Si-Nuclear Magnetic Resonance
spectroscopy, viscosity measurements and infrared spectroscopy. We find that the two routes are fundamentally
different. Increasing the concentration of the sodium silicate system leaves the silica speciation
apparently unchanged. Lowering the pH leads to condensation reactions, thus a change in the silica
speciation.