kieserite

Kieserite is a mineral in the magnesium sulfate family with the chemical formula MgSO4·H2O. It represents the monohydrate form of magnesium sulfate and is part of the suite of evaporite minerals that form in arid environments and saline brines.

Kieserite typically occurs as colorless to white crystals, or as crusts and crusty aggregates. It is usually transparent to translucent with a vitreous luster. It has a relatively low hardness on the Mohs scale and is soluble in water. Like other hydrated magnesium sulfates, kieserite is sensitive to dehydration and can form or change into other hydrates depending on temperature and humidity.

Formation and occurrence often take place in evaporitic settings where concentrated sulfate-rich brines precipitate minerals as water evaporates. Kieserite can coexist with gypsum, anhydrite, and epsomite in evaporite sequences and may arise from direct precipitation or by dehydration of other magnesium sulfate hydrates under changing environmental conditions.

Uses and significance commonly focus on its role as a source of magnesium and sulfur for agriculture. Kieserite is marketed as a fertilizer with a relatively high magnesium content and low chloride levels, making it suitable for crops sensitive to salts. It provides a readily soluble magnesium sulfate source that supports plant nutrition, particularly in soils deficient in magnesium or sulfur.

In summary, kieserite is the magnesium sulfate monohydrate mineral familiar in evaporite geology and in agri-nutrient industries as a magnesium and sulfur fertilizer source.