Commercially valuable potash salts usually occupy only minor parts of evaporite basins, whereas certain noncommercial potassium-bearing minerals have a more widespread distribution.

The processes of the concentration of these potentially valuable salts no doubt begin when salt first is precipitated within the evaporating basin. As brine concentration increases, highly complex solutions are formed which influence not only the chemical but also the physical factors of concentration. Environmental and geologic processes at this time further aid in restricting the depositionally favorable locations in which the potash-bearing solutions can precipitate.

On completion of evaporation and burial of the preserved complex salts, further concentration and enrichment of the potash salts may occur due to metasomatic processes.

Saline precipitation presently is taking place on a reduced scale in some locations along the continental margins of the ocean basins, inland seas, continental brine lakes, and salt pans.

Trace minerals, such as bromine, cesium, and rubidium are of special interest in saline studies, because they furnish much information on the genetic character of the salts. Argon, found commonly in salt sequences where a high concentration of potassium is present, aids in the determination of the age of the salt.

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