A method for recovery of salts, comprising the steps of: - providing a start material, which when brought in contact with water forms an initial aqueous solution comprising ions of Na, K, Cl and optionally Ca; - treating said start material into an enriched aqueous solution having a concentration of CaCl 2 of at least 15% by weight; said treating optionally comprising reduction of water content; and said step of treating generating a solid mix of NaCl and KCl; and - separating said solid mix of NaCl and KCl from said enriched aqueous solution, giving a depleted aqueous solution comprising ions of Ca and Cl as main dissolved substances, characterized in that said treating comprising controlled provision of at least additional ions of Ca into said enriched aqueous solution in excess of what a said initial aqueous solution can provide; and by the further steps of: - adding said solid mix of said NaCl and KCl into an aqueous solution, thereby dissolving at least a part of said solid mix of said KCl and NaCl, to form a mixed aqueous solution; said step of adding said solid mix of said NaCl and KCl into said aqueous solution comprises controlled dissolving said KCl and optionally a part of said NaCl in said aqueous solution at a first temperature to obtain a first concentration of KCl; said first concentration of KCl being lower than a solubility concentration of KCl at said first temperature; and - separating said NaCl and KCl into individual fractions from said mixed aqueous solution; said step of separating said NaCl and KCl into individual fractions in turn comprises the steps of: - separating any solid NaCl from said mixed aqueous solution at said first temperature; - lowering, after said step of separating any solid NaCl, a temperature of said mixed aqueous solution to a second temperature lower than said first temperature; and - separating any precipitated KCl from said mixed aqueous solution at said second temperature; and by the further step of heating and recycling, after said separating of said any precipitated KCl, at least a part of said mixed aqueous solution for a further said adding of said solid mix of said NaCl and KCl. - providing a start material, which when brought in contact with water forms an initial aqueous solution comprising ions of Na, K, Cl and optionally Ca; - treating said start material into an enriched aqueous solution having a concentration of CaCl 2 of at least 15% by weight; said treating optionally comprising reduction of water content; and said step of treating generating a solid mix of NaCl and KCl; and - separating said solid mix of NaCl and KCl from said enriched aqueous solution, giving a depleted aqueous solution comprising ions of Ca and Cl as main dissolved substances, characterized in that said treating comprising controlled provision of at least additional ions of Ca into said enriched aqueous solution in excess of what a said initial aqueous solution can provide; and by the further steps of: - adding said solid mix of said NaCl and KCl into an aqueous solution, thereby dissolving at least a part of said solid mix of said KCl and NaCl, to form a mixed aqueous solution; said step of adding said solid mix of said NaCl and KCl into said aqueous solution comprises controlled dissolving said KCl and optionally a part of said NaCl in said aqueous solution at a first temperature to obtain a first concentration of KCl; said first concentration of KCl being lower than a solubility concentration of KCl at said first temperature; and - separating said NaCl and KCl into individual fractions from said mixed aqueous solution; said step of separating said NaCl and KCl into individual fractions in turn comprises the steps of: - separating any solid NaCl from said mixed aqueous solution at said first temperature; - lowering, after said step of separating any solid NaCl, a temperature of said mixed aqueous solution to a second temperature lower than said first temperature; and - separating any precipitated KCl from said mixed aqueous solution at said second temperature;