Polyhalite
“The multi-nutrient evaporite mineral”
Polyhalite is a hydrated sulfate mineral containing potassium, calcium, magnesium, and sulfur — four essential plant nutrients in one natural mineral. It forms in ancient evaporite sequences and has gained attention as a slow-release, organic-approved fertilizer alternative to conventional potash.
hydrated potassium calcium magnesium sulfate (K₂Ca₂Mg(SO₄)₄·2H₂O)
Zechstein evaporites (Yorkshire, England — massive deposit), Permian Basin (New Mexico/Texas, USA), Stassfurt (Germany), Carlsbad (New Mexico, USA)
2.5-3.5
A vast polyhalite deposit discovered under the North York Moors in England may contain over 2.66 billion tons of the mineral — enough to supply global fertilizer markets for decades and currently the subject of a controversial mining project.
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