Polyhalite is a hydrous potassium calcium magnesium sulfate mineral known for its white to grayish color, with occasional reddish or yellowish tints. This mineral exhibits a vitreous to pearly luster and commonly forms as compact masses or irregular granular aggregates. Polyhalite belongs to the sulfate class of minerals and is a member of the evaporite group, often found in association with other evaporite minerals such as halite, sylvite, and anhydrite.


Polyhalite has a number of applications, primarily as a source of potassium, magnesium, and sulfur in the production of fertilizers. Its unique combination of nutrients makes it an effective and valuable agricultural resource, contributing to improved crop yield, quality, and resistance to environmental stresses. Additionally, polyhalite is sometimes used in the manufacturing of cement, where it can help to regulate the setting time and enhance the properties of the final product.


Polyhalite forms through the evaporation of mineral-rich brines in sedimentary basins, where it precipitates from the concentrated solutions. This process typically occurs in arid environments, where the rate of evaporation exceeds the rate of water input. Over time, the precipitation of polyhalite and other evaporite minerals leads to the formation of layered deposits.


Polyhalite is primarily found in evaporite deposits, where it occurs alongside other evaporite minerals such as halite, sylvite, and anhydrite. Some of the most significant deposits of polyhalite can be found in the United States, Germany, and the United Kingdom, particularly in the Permian Basin and the Zechstein Basin. These areas are known for their extensive evaporite deposits, resulting from the evaporation of ancient seas and salt lakes in geologically favorable environments.


Although polyhalite is not widely recognized in metaphysical and spiritual practices, its unique combination of elements might be interpreted as symbolizing balance and harmony. The interconnectedness of potassium, calcium, magnesium, and sulfur within the mineral could be seen as a reminder of the interconnectedness of all things in the universe. Polyhalite could potentially be used as a tool for grounding, promoting stability, and encouraging a sense of connectedness with the natural world.

LusterVitreous to pearly
Hardness (Mohs)3.5
ColorWhite, grayish, occasionally reddish or yellowish
CleavagePerfect in one direction, good in another
Specific Gravity2.78 – 2.80