2580 Since the discovery of new potential lithium-bearing areas, Brazil has emerged as an important supplier of hard-rock lithium, particularly in the Eastern Brazilian Pegmatite Province (Minas Gerais), widely known as the “Lithium Valley.” Recent technical reports and pilot-scale studies indicate that most Brazilian projects rely predominantly on gravity-based pre-concentration, particularly Dense Media Separation (DMS), reflecting the coarse-grained mineralisation and favourable density contrast between spodumene and gangue minerals. Table 1 summarises key processing parameters reported for selected Brazilian lithium projects, located in Minas Gerais. Table 1 – Summary of processing routes and metallurgical performance of selected Brazilian lithium projects Project (Location) Main Process ROM (% Li₂O) Concentrate (% Li₂O) DMS Top Size (mm) Recovery (%) Development Stage Grota do Cirilo (Araçuaí/Itin ga) Crushing + DMS + magnetic ~1.3–1.5 5.5–6.0 ~10–12 >70 global Operating mine Salinas (Salinas) DMS 1.38 5.5 +1 to ~6.3 93 stage Pilot Scale Volta Grande (Nazareno) Crushing + gravity + magnetic + flotation ~1.0–1.1 5.5–6.4 Not applied Not detailed Operating mine Bandeira (Bandeira) DMS 1.2–1.4 5.5–6.0 ~10 Preliminary projections Pilot/Prefeasibility Cachoeira (Araçuaí) Crushing + DMS + attrition + flotation ~1.2–1.6 5.5–6.2 not detailed ~75–80 global Operating mine Neves (Governador Valadares) Heavy liquid separation tests (>0.25%) Under evaluation P100 ~30 Preliminary Exploration From Table 1, it can be verified that economically viable Brazilian spodumene deposits typically have head grades of 1.0-1.5% Li₂O. Second, the grade concentrate targets 5.5–6.4% Li₂O consistently. Recoveries vary with mineralogical deposit characteristics: operating mine reports indicate global recoveries above 70%, whereas pilot tests demonstrate stage recoveries exceeding 90% for coarse fractions. DMS is the dominant processing method in Brazil due to the coarse spodumene crystal size and the pronounced specific-gravity contrast with gangue minerals. With the aim of increasing knowledge about Brazilian pegmatites and the application of DMS for concentrating lithium minerals, this study presents a case study from southeastern Brazil. Lithium-bearing minerals from Minas Gerais were characterised through chemical and mineralogical analysis, and preliminary sink-and-float tests were executed. 2. METHODOLOGY 2.1 Samples The samples were from a pegmatite deposit located in Minas Gerais, Brazil. Approximately 1.50 kg of material was prepared for this case study. The material was homogenized and quartered to obtain
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