Metazeunerite is an arsenate mineral with a chemical formula of Cu(UO₂)₂(AsO₄)₂·8H₂O. The origin of this mineral is almost always from the natural

dehydration In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild deh ...

process of zeunerite. It is named for civil engineer Gustav A. Zeuner, who worked at the School of Mines in

Freiberg Freiberg () is a university and former mining town in Saxony, Germany, with around 41,000 inhabitants. The city lies in the foreland of the Ore Mountains, in the Saxon urbanization axis, which runs along the northern edge of the Elster and ...

and its lowered hydration state.

Properties

Its crystal system is tetragonal and its crystal class is 4/m, which is also called the tetragonal-dipyramidal class because it only has a vertical four-fold rotation axis that is perpendicular to the symmetry plane. When looking at a thin section, metzeunerite is anisotropic, meaning that it has pleochroism. When a mineral is anisotropic, one can see whether it is uniaxial or biaxial, depending on how fast the rays of light are moving through the mineral. This mineral is uniaxial negative due to the ordinary ray being slower than the extraordinary ray.

Occurrence

Metazeunerite is an uncommon radioactive secondary mineral found in "arsenic bearing hydrothermal uranium deposits" across the world. This widespread mineral occurs specifically in Europe, western North America, Australia, Brazil and Chile, Namibia, and Kazakhstan. It is currently studied through thermal decomposition by calculating the different levels of dehydration, as zeunerite is transformed into metazeunerite. Metazeunerite was shown to be an important solubility limiting phase controlling uranium migration in the soils of the UK's only, and now abandoned, uranium mine, South Terras, located near

St Stephen-in-Brannel St Stephen-in-Brannel (known locally as ''St Stephen's'' or ''St Stephen'') () is a civil parish and village in mid Cornwall, England. The village is four miles (6.5 km) west of St Austell on the southern edge of Cornwall's china clay dis ...

References

Bibliography

*Palache, P.; Berman H.; Frondel, C. (1960). "''Dana's System of Mineralogy, Volume II: Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. (Seventh Edition)"'' John Wiley and Sons, Inc., New York, pp. 993–994. {{Commons category Arsenate minerals Copper(II) minerals Uranium(VI) minerals Tetragonal minerals Minerals in space group 85