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Hazenite

Hazenite
General
Category Phosphate mineral
Struvite group
Formula
(repeating unit)
KNaMg2(PO4)2·14H2O
Strunz classification 8.CH.40
Dana classification 40.01.01.03
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H–M Symbol: (2/m 2/m 2/m)
Space group Pmnb
Unit cell a = 6.9349, b = 25.1737
c = 11.2189 [Å]; Z = 4
Identification
Formula mass 276.331 g/mol
Color Colorless
Crystal habit Radiating elongated tabular or prismatic clusters or single bladed tabular crystals
Cleavage {001} Good
Tenacity Brittle
Mohs scale hardness 2 - 2.5
Luster Vitreous
Streak White
Diaphaneity Transparent
Specific gravity 1.91
Optical properties Biaxial (+)
Refractive index nα =1.494(1), nβ = 1.498(1), nγ = 1.503(1)
2V angle 41°
Dispersion Strong r < v
Solubility In water
References

Hazenite is a hydrous phosphate mineral with chemical formula of KNaMg2(PO4)2·14H2O, therefore a hydrous alkali magnesium phosphate. It is a member of the struvite group.

It was first described for an occurrence adjacent to Mono Lake, California, and named after Robert M. Hazen 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.

It occurs as crystal clusters associated with decomposed algae remnants on calcite or aragonite. It is precipitated by microbes in the highly-alkaline environment of Mono Lake.



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