TUNGSTENITE

    Class : Sulfides and sulfosalts
    Subclass : Sulfides
    Crystal system : Hexagonal
    Chemistry : WS2
    Rarity : Very rare

Tungstenite is an extremely rare tungsten sulfide. It is found in tungsten deposits (high-temperature hydrothermal veins, skarns or replacement deposits); its primary or secondary origin divides specialists. Its name is linked to its chemical composition. It is the tungsten equivalent of molybdenite from which it has borrowed the lamellar structure and the dark gray to black color. The lamellae of tungstenite are, however, notably smaller than in molybdenite and often grouped in fine scaly aggregates. Of low hardness (2.5), it is a mineral that stains the fingers.

Main photo : Tungstenite from Nedre Lapplægeret Quarry, Norway © OT. Ljøstad

Tungstenite in the World

Tungstenite is known from the Emma Mine (Utah), from the large Canadian deposit of Kidd Creek (Ontario), and from Tsumeb (Namibia).

Right photo : Tungstenite from Crevoladossola Quarry, Piemond, Italy © Paolo Sburlati


Tungstenite in France

In France, tungstenite is known as a rarity in the small wolframite and arsenopyrite veins of Bosberty (Puy-de-Dôme).

Twinning

No twinning known for this mineral species.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 2.5
Density : 7.40
Fracture : Undetermined
Streak : Lead gray

TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None

Solubility : Aqua regia

Magnetism : NoneRadioactivity : None