Carnallite

Carnallite is a hydrated potassium-magnesium chloride mineral, KMgCl₃·6H₂O, found in evaporite deposits and mined as a source of potash.

Evaporite: A sedimentary deposit of minerals left behind when saline water evaporates. Carnallite forms late in the evaporation of concentrated brines.
Fractional crystallization: The sequential formation of crystals as a solution’s composition changes during cooling or evaporation. Successive salt precipitation concentrates the remaining brine until carnallite can form.
Fertilizer: A material added to soil or plants to supply nutrients and support growth. Potassium recovered from carnallite is used in crop fertilizers.
Zechstein: A Late Permian sequence of evaporite rocks deposited across parts of northern and central Europe. Zechstein strata contain substantial potash minerals, including carnallite.
Potash: Water-soluble potassium salts used mainly in fertilizers and industrial processes. Carnallite is mined and processed to recover potassium for potash products.
Solubility: The extent to which a substance dissolves in a particular solvent under specified conditions. Changing temperature and brine composition can dissolve or precipitate carnallite.
Potassium chloride fertilizer: A potassium-rich fertilizer made primarily from potassium chloride, commonly called muriate of potash. It is a major agricultural product made from carnallite-derived potash.
Dead Sea: A hypersaline lake bordered by Jordan, Israel, and the West Bank. Its concentrated brines and salt deposits illustrate modern potassium-magnesium salt formation.
Halide mineral: A mineral composed of halide anions combined with metal or metalloid cations. Chloride ions make carnallite part of this mineral class.
Dehydration: The removal of water from a substance by physical or chemical means. Heating carnallite can drive off its bound water and alter the material.

Linked from 5 pages