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Leaching of celestite in acidic chloride medium with high efficiency.  Determination of the optimum concentrations of HCl and NaCl.  Precipitation of strontium in the highly acidic chloride solution as strontium carbonate. Celestite (SrSO4) concentrates are difficult to process using solutions prepared with basic acids in classical leaching techniques. In this study, the presence of BaCl2 in the acidic chloride leach solution is provided to the leaching of SrSO4. In the first stage, the dissolution properties of natural celestite ore in solutions prepared with HCl acid, NaCl, and BaCl2 salts were investigated. During the leaching process, the effects of time, solid/liquid ratio, temperature, HCl and NaCl concentrations on leaching the efficiency were investigated. The highest leaching efficiency obtained was 91.2% with solid/liquid ratio of 1/300 at 65°C in a solution containing 0.5 M HCl and 1M NaCl. In the second step, the SrCO3 was precipitated from the solution obtained from the dissolution experiments. The effect of different temperature values (25-75°C) on the precipitation efficiency was investigated. At 75°C, 99.5% of the strontium ions in the solution could be precipitated by addition of sufficient Na2CO3. Figure A. a) Flow chart of the experimental study b) Graph for the yield of leaching vs time at different temperatures-Solid/Liquid ratio: 1/300; [HCl]: 0.5 M; [NaCl]: 1.0 M. Purpose: The purpose of this study is to dissolve the celestite ore which is insoluble in basic acids with a classical leaching process and then to precipitate SrCO3 from this solution. Theory and Methods: The leaching of the Turkish celestite was performed by dissolving in the medium prepared with NaCl, HCl, and BaCl2. Subsequently, the SrCO3 precipitated by adding Na2CO3 solution. Results: Celestite solubility was improved, at high temperatures especially at 65°C and 85°C. Rising of the solid/liquid ratio caused the leaching yield to decrease. The maximum solubility is achieved in the solution prepared with 1 M NaCl and 0.5 M HCl, nevertheless, at higher chloride concentrations, the solubility decreases as saturation is achieved. Conclusion: The celestite could be leached with a yield of 91.2% in the presence of stoichiometric BaCl2 in the solution prepared with 0.5 M HCl and 1 M NaCl and at a solid/liquid ratio of 1/300 at 65°C. Then SrCO3 was precipitated from the acidic chloride solution using excess Na2CO3 with a yield of 99.5%.