Dark brownish red hübnerite crystals with quartz (4.0 × 3.0 × 2.7 cm). Found from Pasto Bueno, Ancash, Peru — Photo: Ivar Leidus · CC BY-SA 4.0
Hübnerite
Also known as: Huebnerite.
The manganese end-member of the wolframite series — manganese tungstate, an important tungsten ore.
Intro adapted from Wikipedia (CC BY-SA).
Hübnerite is an IMA-recognized mineral species in the tungstate class, with the chemical formula Mn²⁺(WO₄).
It crystallizes in the monoclinic crystal system (space group P2/c). It is a member of the Wolframite structural group.
Key properties: Mohs hardness 4–4.5; specific gravity 7.12–7.18; typically brown or black or red; Yellow to reddish brown, greenish gray streak; Metallic-adamantine towards resinous luster; refractive index 2.243; optically biaxial.
IMA symbol Hbr, grandfathered status — known before the IMA’s founding, named in 1865.
Typical of high-temperature hydrothermal vein deposits and pneumatolytically altered granites yielding greisen; in granite pegmatites; also in alluvial and eluvial deposits.
It is found associated with Cassiterite, arsenopyrite, molybdenite, tourmaline, topaz, rhodochrosite, fluorite.
The mineral was named to honor Adolph Hübner, metallurgist of Freiberg, Germany.
Collections: Metals & Native Elements, Collector Favorites.