<![CDATA[The development of environmentally friendly construction materials has become one of the key efforts to reduce dependence on Portland cement, which significantly contributes to global carbon emissions. This study aims to characterize the constituent materials of a geopolymer system based on fly ash, hydrated lime, and lateritic soil sourced from Gowa Regency, South Sulawesi, and Baubau City, Southeast Sulawesi, Indonesia. The research employed a quantitative experimental approach through the analysis of the physical, chemical, and microstructural characteristics of the materials. Physical characterization included moisture content, specific gravity, Atterberg limits, and particle size distribution tests, while chemical and microstructural characterization was conducted using X-Ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM). The results indicated that the lateritic soils were predominantly composed of fine particles, with Al₂O₃ as the major component in the Gowa sample (49.38%) and SiO₂ as the dominant component in the Baubau sample (67.82%). The fly ash samples exhibited high contents of SiO₂, Al₂O₃, and Fe₂O₃, while the Jeneponto fly ash contained a higher CaO content than the Baruta fly ash. SEM observations revealed particle morphologies that have the potential to support the geopolymerization process. Overall, the combination of lateritic soil, fly ash, and hydrated lime demonstrates favorable characteristics for utilization as locally sourced geopolymer raw materials, offering a promising alternative for sustainable and environmentally friendly construction materials.]]>
