Class : Carbonates, nitrates, borates
    Subclass : Nitrates
    Crystal system : Orthorhombic
    Chemistry : KNO₃
    Rarity : Common

Niter (or saltpeter) is a mineral known since ancient times: it is the basis for the manufacture of black powder because it has the property of deflagrating violently when heated. Its name is derived from the Greek nitron and the Latin nitrium (potassium nitrate, saltpeter), themselves deriving from the Hebrew neter. It is a water-soluble salt which is found mainly in acicular crystals, small and delicate, grouped in efflorescences, silky or earthy, and in encrustation of white color and glassy luster on the soil of desert regions. Niter is also formed in efflorescence in damp places (caves, cellars, underground passages, etc...). It is an important source of nitrogen, mainly for the manufacture of fertilizers, explosives and plastics.

Main photo : Synthetic niter crystals (precipitation from saturated solution)

Twins are common on {110} forming pseudo-hexagonal crystals.

No fakes recorded for this mineral species.