The morphological analysis of silica gel synthesized from river and beach sand magnetic
minerals was carried out, with samples taken from Pringgabaya Beach, East Lombok,
Indonesia. The sol-gel method with NH4OH variation (7 M, 8 M, 9 M, and 10 M) was
utilized as the synthesis method. Morphological characterization was conducted via a
scanning electron microscope, mineral content analysis using energy dispersive X-ray,
dielectricity analysis through parallel plates, and resistivity analysis via the two-point probe
method. The morphology of the resulting silica gel is granular, with the grain size of each
NH4OH variation found to be 1.741 at 7 M, 1.676 at 8 M, 1.583 at 9 M, and 1.496 nm at
10 M. It appears that the greater the concentration of NH4OH, the smaller the grain size of
the resulting silica gel because with greater NH4OH concentration, NH4OH will have more
energy to break down silica during synthesis via the sol-gel method. Moreover, the larger
the grain size of silica gel, the smaller the dielectric constant and resistivity values.