A less harmful approach for the environment regarding chalcopyrite concentrate leaching,using seawater/brine and caliche’s salts as a source of chloride and nitrate ions, was investigated.Dierent variables were evaluated: sulfuric acid concentration, sodium nitrate concentration, chlorideconcentration, source of water (distilled water, seawater, and brine), temperature, concentrate sampletype, nitrate source (analytical grade and industrial salt), and pre-treatment methods in order toobtain maximum copper extraction. All tests were performed at moderate temperatures (45 C)and atmospheric pressure. The leaching system using distilled water, seawater, and brine basemedia resulted in copper extraction of 70.9%, 90.6%, and 86.6% respectively. The leaching media,with a concentration of 20 g/L Cl􀀀, obtained a maximum Cu extraction of 93.5%. An increase in theconcentration of H2SO4 and NaNO3 from 0.5 to 0.7 M, led to an increase in the copper extraction.The use of an industrial salt compared to the analytical salt did not show great variations in thepercentage of extraction achieved, which would be a good and cost eective alternative. The increasein temperature from 25 to 45 C showed a great eect on the copper leaching (of 60% until 90.6%,respectively). The pre-treatment is suggested to increase copper extraction from 60.0% to 71.4%.