The microstructure of the starting hydrogel has extremely important role in the synthesis of the microporous materials. Due to the fact that very limited number of experimental methods (techniques) can be used for gel analysis, there are still a lot of missing informations about the processes on molecular level, which occur before and during the nuclei formation. In this paper, various methods were used in characterization of pretreated (aged) hydrogel before the process of its hydrothermal transformation to zeolite A. Results show the changes in chemical composition and in microstructure of the solid phase (FTIR, PALS, BET, DTG), indicating that the structure of the ordered phase (potential nuclei) within gel matrix (completely amorphous according to PXRD patterns) is rather of different structural units typical for FAU and SOD (or their mixture) than the final product (LTA) only!