| Summary: | The research is dealing with lateritization and geochemistry of nickel deposits formed from ultramafic rock. This study consists of field work and laboratory analysis. The seven core drilling samples where analysed. Totality drill core assay including in the analysis is 304 data. The aim or research is to understand the lateritization control factor and geochemistry behavior of elements during lateritization, and its relationship to differences of quality (grade) and quantity (thickness) of lateritic nickel in exploration block 2F1 and 2F3 of PT. BintangDelapan Mineral in Bahodopi, Morowali Regency, Central Sulawesi.
Lateritization consists of red limonite, yellow limonite, saprolite and berdrock, based on the result of mineralogy and geochemistry analysis of core samples: Red limonite zone is dominated by hematite mineral with Ni<0.8%, Co<0.1%, Fe>50% and MgO<0.5%, yellow limonite is dominated by goethite mineral with Ni 0.8-1.5%, Co 0.1-0.2%, Fe 40-50% and MgO 0.5-5%, saprolite is dominated by serpentine mineral group with Ni�1.5%, Co<0.02-0.1%, Fe 10-40%, and MgO 5-35%, and the bedrock consists lherzolite composed of olivine, pyroxene, serpentine and opaque mineral with Ni<0.8%, Co 0.01%, Fe 5-10%, and MgO�35%..
Genetically, Morphology controlled the quality and quantity of lateritic nickel deposits, in research area. Areas with flat slopes to the middle are more enriched in nickel rather than those of steep slope, as in addition lateritic deposits formed, in the flat to the middle is thicker than those of steep area.
Geochemistry behavior of lateritic elements indicates that the higher chemical weathering is increasing with the depth decrease, dispersion of geochemistry element indicates Ni, MgO, SiO2, and Co, is mobile, Fe, Al2O3, Cr2O3 is immobile. The mass balance calculation indicates the addition of Ni grade increases up to 315% (10.054 kg/m3), Fe = 286% (180.765 kg/m3), Co = 243% (986kg/m3), Al = 340% (8,923 kg/m3), Cr = 144% (1,303 kg/m3), whereas Mg grade decrease up to 99% (158kg/m3), Si also has 99% (188 kg/m3
Control factors of lateritization and geochemical behavior controlled the formation of lateritic nickel deposits in the research area in order to produce qualitative and quantitative differences between block 2F1 and 2F3.
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