Hübnerite

Hübnerite or hubnerite is a mineral consisting of manganese tungstate (chemical formula: MnWO₄). It is the manganese endmember of the manganese - iron wolframite solid solution series. It forms reddish brown to black monoclinic prismatic submetallic crystals. The crystals are typically flattened and occur with fine striations. It has a high specific gravity of 7.15 and a Mohs hardness of 4.5. It is transparent to translucent with perfect cleavage. Refractive index values are nα=2.170 - 2.200, nβ=2.220, and nγ=2.300 - 2.320.

Typical occurrence is in association with high-temperature hydrothermal vein deposits and altered granites with greisen, granite pegmatites and in alluvial deposits.

It was first described in 1865 and named after the German mineralogist, Adolf Huebner.

ee also

*List of minerals
*List of minerals named after people

References

* [http://mineral.galleries.com/minerals/sulfates/huebneri/huebneri.htm mineral galleries]
* [http://webmineral.com/data/Hubnerite.shtml webmineral.com]
* [http://www.mindat.org/min-1940.html Mindat data]