Hazenite is a hydrous

phosphate mineral Phosphate minerals contain the tetrahedrally coordinated phosphate (PO43−) anion along sometimes with arsenate (AsO43−) and vanadate (VO43−) substitutions, and chloride (Cl−), fluoride (F−), and hydroxide (OH−) anions that also fit i ...

with chemical formula of , therefore a hydrous alkali magnesium phosphate. It is a member of the

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 platy mica-like forms. It is a soft m ...

group. It was first described for an occurrence adjacent to Mono Lake,

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, and named after

Robert M. Hazen Robert Miller Hazen (born November 1, 1948) is an American mineralogist and astrobiologist. He is a research scientist at the Carnegie Institution of Washington's Geophysical Laboratory and Clarence Robinson Professor of Earth Science at George ...

of the Carnegie Institute. It was approved as a new mineral on February 28, 2008 by the Commission on New Minerals of the

International Mineralogical Association Founded in 1958, the International Mineralogical Association (IMA) is an international group of 40 national societies. The goal is to promote the science of mineralogy and to standardize the nomenclature of the 5000 plus known mineral species. Th ...

. It occurs as crystal clusters associated with decomposed

cyanobacteria Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blu ...

remnants on

calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...

or aragonite. It is precipitated by microbes when the lake has been dry for so long that phosphorus levels build up, poisoning the microbes. They dispose of the excess phosphorus by excreting hazenite crystals. The crystals disappear when it rains or the lake level rises.

References

{{reflist Potassium minerals Sodium minerals Magnesium minerals Phosphate minerals Orthorhombic minerals Minerals in space group 62