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NITRATES · ORTHORHOMBIC

Niter

About

Niter, along with Nitratine, are unusual minerals belonging to the nitrates group. These two nitrate minerals can be visually indistinguishable, with the ancient term Niter used to describe both Niter and Nitratine. Nitratine is actually the more prevalent and economically important member of the group.
Niter is a very fragile mineral, and is poorly represented in collections. Its solubility in water restricts its occurrence to caves where it receives protection from rain. Niter often forms as powdery growths on cavern walls, and doesn't usually form in good crystals. Large crystals are not natural, and are easily grown synthetically.
Niter original name source is from the ancient Hebrew word "neter", where it is described as cleaning agent in biblical sources.

Crystal Forms & Aggregates

Most of often as thin encrusting aggregates and as short and delicate acicular fibers covering rock or cavern surfaces. Hexagonally-shaped twinned crystals are also found.

Other ID Marks

1) Soluble in water.2) Has a peculiar cooling taste.

Striking Features

Unique habit of formation, taste

Environment

Uses

Niter, along with Nitratine, are mined as nitrous compounds for the production of fertilizer, and have also been a source for gunpowder. Nitrate mining has been on the decrease as much of the world's demand for nitrates are now met by synthetically produced nitrates.

Noteworthy Localities

Niter has been mined in several of the cave systems of Alabama, Kentucky, Tennessee, and Virginia. Niter is also found and mined, along with Nitratine, in several locations in the Atacama Desert, Antofagasta Province, Chile (Tarapacá and Antofagasta provinces.)
Specimen-worthy, rosette-shaped aggregates, and fibrous "blooms" and crusts are found in Crimea, Ukraine, at Bakla Mountain, Skalistoye.

Common Mineral Associations