How do I identify Struvite?

Struvite can be identified by its hardness of 1.5 - 2 on the Mohs scale, Colourless color. Look for these key characteristics when examining specimens.

What color is Struvite?

Struvite typically appears in Colourless, white (dehydrated), yellow or brownish, light grey; colourless in transmitted light.. Color can vary depending on impurities and formation conditions.

How hard is Struvite?

Struvite has a hardness of 1.5 - 2 on the Mohs scale. This makes it a soft mineral that can be scratched easily.

Struvite

A variety of Minerals

What is Struvite?

Struvite (magnesium ammonium phosphate) is a phosphate mineral with formula: NH4MgPO4·6H2O. Struvite crystallizes in the orthorhombic system as white to yellowish or brownish-white pyramidal crystals or in platey mica-like forms. It is a soft mineral with Mohs hardness of 1.5 to 2 and has a low specific gravity of 1.7. It is sparingly soluble in neutral and alkaline conditions, but readily soluble in acid. Struvite urinary stones and crystals form readily in the urine of animals and humans that are infected with ammonia-producing organisms. They are potentiated by alkaline urine and high magnesium excretion (high magnesium/plant-based diets). They also are potentiated by a specific urinary protein in domestic cats.

Uses & Applications

There is considerable interest in the utility of urine-derived struvite as a fertilizer in austere situations.

Struvite Market Value Calculator

Estimate the market value of Struvite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.

Struvite Localities Map

See where Struvite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.

Map preview

North ZoneCentral RidgeSouth Basin

Key Characteristics

Formation of Struvite

Struvite is occasionally found in canned seafood, where its appearance is that of small glass slivers, objectionable to consumers for aesthetic reasons but of no health consequence. A simple test can differentiate struvite from glass. Use of struvite as an agricultural fertilizer was in fact first described in 1857.

Quick Facts

Physical Properties

Color: Colourless, white (dehydrated), yellow or brownish, light grey; colourless in transmitted light.
Hardness (Mohs): 1.5 - 2
Density: 1.705 g/cm³
Streak: White