Brine mining is the extraction of useful materials (elements or compounds) which are naturally dissolved in brine. The brine may be seawater, other surface water, groundwater, or hyper-saline solutions from several industries (e.g., textile industries). It differs from solution mining or in-situ leaching in that those methods inject water or chemicals to dissolve materials which are in a solid state; in brine mining, the materials are already dissolved.