<p>This study analyzed the effect of Zn²⁺ amount on the formation of zinc silicate phases synthesized from natural silica using a hydrothermal method, a parameter that has not been explored before. Utilizing natural silica as an environmentally friendly precursor, we assessed the composition and phase characteristics of samples containing varying amounts of Zn²⁺. Characterization focused on the composition, morphology, thermal properties, and optical behavior of the samples. The results indicate that the sample with the addition of 25% Zn²⁺ consisted of 72.3% zincite (ZnO) and 27.7% hemimorphite (Zn₄Si₂O₇(OH)₂). In contrast, the sample with 50% Zn²⁺ contained 47.3% hemimorphite and 52.7% willemite (Zn₂SiO₄). Furthermore, we evaluated the photocatalytic performance of each sample for methylene blue degradation under visible light, achieving a degradation efficiency of 96.62% within 120&#xa0;min, thus becoming a promising material in photocatalysis applications, particularly in the treatment of dye wastewater.</p>