Industrial Potential and Geochemical Characterization of Diatomite Resources in the Ethiopian Rift Area: Value Addition and Strategic Economic Applications

The Ethiopian Rift System, a segment of the broader East African Rift, serves as a significant repository for industrial minerals, among which diatomite stands out as a resource of high economic potential. This comprehensive review examines the geological occurrence, geochemical and mineralogical profiles, and industrial utility of Ethiopian diatomite, primarily concentrated in the Main Ethiopian Rift and the Afar Depression. With estimated reserves exceeding 46.53×106 metric tons, the deposits are characterized by high amorphous silica content, ranging from 76.4% to over 86% in their raw state, and reaching upwards of 96% through thermochemical purification. Mineralogical investigations identify Opal-A as the primary silica phase, with a diverse assemblage of benthic freshwater diatom species, including Staurosirella pinnata and Staurosira construens. The material exhibits exceptional physical properties, such as low bulk density (0.32–0.42 g/cm³) and high porosity (up to 85.6%), rendering it suitable for traditional applications in filtration, insulation, and as a lightweight filler. Furthermore, this review highlights transformative value-addition opportunities in advanced manufacturing, including 3D concrete printing for carbon sequestration and geopolymer foams for thermal energy storage. Strategic alignment with Ethiopia's 10-year development plan (2021–2030) suggests that local processing and import substitution could save significant foreign currency and catalyze regional industrial growth. However, the location of these deposits within sensitive lacustrine ecosystems, such as the Abiyata-Shala Lakes National Park, necessitates a balanced approach to development that integrates rigorous environmental impact assessments and sustainable mining practices.