2581 representative subsamples for chemical analysis, mineralogical studies, and heavy liquid separation tests. 2.2 Mineralogical Studies An approximate 0.75 kg ore subsample was divided into two particle size fractions: +850 μm and 850/+500 μm. This particle size fraction was defined due to the limitations in the applicability of methods in static dense media separation, which have a lower limit of 500 μm. Samples from each fraction were utilized to prepare epoxy sections through a cold-embedding process, followed by multiple polishing stages using electric, wet hand, and diamond polishing techniques. After polishing, the surfaces were carbon-coated to enhance conductivity. The polished sections were then examined using Scanning Electron Microscopy (Hitachi FlexSEM 1000) to assess mineral morphology and determine the mineralogical composition. In SEM-based automated mineralogy, mineralogical quantification is performed using Energy-Dispersive Spectroscopy (EDS), which identifies the chemical composition of particles. However, SEM-EDS systems have limitations in detecting elements lighter than carbon, such as hydrogen and lithium, due to the low energy of their characteristic X-rays, which affects system performance. Consequently, the chemical quantification of lithium-bearing minerals was estimated based on the presence of Al-Si-O (Kundu et al., 2023). 2.3 Heavy Liquid Separation Studies Heavy liquid separation (HLS) studies were performed using Bromoform (density of 2.89 g/cm³) across an interval of specific gravities (S.G.) from 2.60 to 2.89, in increments of 0.10 S.G. Approximately 0.75 kg of the sample was sieved to a particle size between -850 µm and +500 µm, and around 20 g of this subsample (in three replicates) was placed into 50 mL of heavy liquid with a SG of 2.89 within a separatory funnel. After separation, the sink product was collected through the funnel opening, while the float product was collected separately. The float product obtained from the initial test was utilized in the next round of tests with a lower heavy liquid S.G. of 2.80, achieved through dilution with ethyl alcohol. This procedure was repeated for S.G. of 2.70 and 2.60. Following the HLS studies, the sink-and-float products were washed with ethyl alcohol to remove residual heavy liquid. The samples were then filtered, dried, weighed, and prepared for ICP-OES analysis. 2.4 Chemical Studies Chemical studies were conducted using Inductively Coupled Plasma Optical Emission Spectroscopy (Optima 8300 ICP-OES from Perkin Elmer). Samples of feed and products from the sink-andfloat tests were initially pulverized and subsequently prepared for ICP-OES to quantify the concentrations of Li2O, Fe2O3, CaO, K2O, Na2O, P2O5, SiO2, Al2O3, MgO, MnO, TiO₂, F, Ta₂O₅, Nb₂O₅, Sn, and S. 3. KEY RESULTS 3.1 Mineralogical Studies According to Figueiredo et al. (2025), the pegmatite sample analyzed through X-ray diffraction (XRD) is composed primarily of gangue minerals, with quartz being the dominant mineral (density: 2.652.70 g/cm³). Additionally, the sample contains albite (2.62 g/cm³), spodumene (3.03-3.23 g/cm³), muscovite (2.76-3.00 g/cm³), and microcline (2.54-2.63 g/cm³). Mineralogical data for the two size fractions (+850 and -850/+500 µm) were evaluated by SEM and derived from EDS chemical analyses. The SEM micrographs reveal, in both size fractions, the presence of spodumene, quartz, fluorite, lithium mica (lepidolite), and microcline. Figures 1 and 2 show examples of the particles found in the SEM analysis.
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