Why are hot brines more effective than pure water at carrying ore minerals?

Pure water is an ineffective solvent for most ore minerals, making it incapable of forming significant hydrothermal mineral deposits.1

In contrast, hot brines—specifically sodium-calcium chloride brines—are highly effective solvents. These solutions are capable of dissolving and transporting a wide variety of sulfide and oxide ore minerals, as well as native metals like gold and silver. The presence of these dissolved salts significantly enhances the chemical capacity of the water to hold metallic minerals in solution, allowing them to be transported through the Earth’s crust until they precipitate in a restricted space to form a deposit.12