KARAKTERISTIK GEOKIMIA ENDAPAN NIKEL LATERIT DAERAH BENTE KECAMATAN BUNGKU TENGAH KABUPATEN MOROWALI PROVINSI SULAWESI TENGAH = GEOCHEMICAL CHARACTERISTICS OF LATERITE NICKEL DEPOSIT IN BENTE AREA, BUNGKU TENGAH DISTRICT, MOROWALI DISTRICT, CENTRAL SULAWESI PROVINCE

Today nickel is one of the mixed metal materials that is needed in the industrial world. The many uses of nickel make the need for this material increase. It was recorded that in 2019 the world's consumption of primary nickel was 2.41 million tonnes, this value has increased by 4.4% compared to 2018 and has continued to increase since 2021. This research was conducted by Laboratory analysis includes sample preparation in the form of thin section preparation which aims to be able to analyze the type of rock and the mineral content present in the rock. X Ray Fluorescence (XRF) analysis to determine chemical elements such as Ni, Fe, Mg, Al, Si, Co, Mn, Cr, and Ca. As well as X Ray Diffraction (XRD) analysis to determine the mineral composition of the sample.
The assay results for the chemical content of Ni, Fe, MgO, Al, Mn, Cr, SiO2 etc., indicate normal laterite in general. Comparison of Fe2O3 – MgO – SiO2 levels shows that the sample group is included in Limonite. Petrographic analysis showed that the rock sample with code SGCA05 was Serpentinized Lherzolite rock with the main mineral composition being Olivine 17 – 25%, Orthopyroxine 12 – 20%, Clinopyroxine 5%, Krom-spinel 2 – 3% and Serpentine 50 – 60%. Thin sections of SGCA07 rock show serpentinite with the mineral composition of Serpentine 85 – 95%, Talc 10% and Krom-spinel 2 – 5%. Samples with code SGCD11 show Hazburgite rocks with the mineral composition of 30-35% olivine, 10-20% orthopyroxine, 2% chrome-spinel and 40-53% serpentine. Analysis of the SiO2/MgO content ratio and LOI showed that the rocks in the study area experienced medium to strong serpentinization.
The distribution of chemical elements and compounds in the study area can be viewed horizontally and vertically where the horizontal distribution can be seen on the distribution map which shows high levels of Fe and Cr2O3 in the southeastern part, high levels of Al2O3 and SiO2 elements in the southwestern part. Elemental Ni is high in the southwest and southeast, MgO is high in the northwest and southeast of the study area. The vertical distribution can be seen in the Hand Auger log where it can be observed that the levels of elements Ni, Al2O3, and Sio2 increase with increasing depth, while the elements Fe, Cr2O3, and MgO experience a decrease in levels with increasing depth

Keywords : XRD, XRF, Nickel Laterite, Mineralization