Ferritungstite - Encyclopedia
Class : Sulfates, chromates, molybdates
Subclass : Tungstates
Crystal system : Cubic
Chemistry : (W,Fe)2(O,OH)6 nH2O
Rarity : Uncommon
Ferritungstite is an uncommon mineral, formed by surface alteration of wolframite and scheelite. It was named thus in reference to its chemical composition (iron + tungsten). Formerly considered a species in its own right, it is today described as a variety of ferric hydrokenoelsmoreite. It usually constitutes orange to brownish powdery coatings, associated with tungstite, in the oxidized superficial parts of hydrothermal tungsten deposits (high temperature veins, skarns, stratoid deposits, etc...).
Main photo : Ferritungstite from Hingston Down Quarry, Cornwall, England © Ian Jones
Ferritungstite in the World
Twinning
A cyclic twin with 6 faces according to the spinel twin law and known as well as an interpenetration twin.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 3
Density : Undeterminated
Fracture : Irregular
Streak : White
TP : Opaque
RI : 2.24
Birefringence : 0
Optical character : None
Pleochroism : None
Fluorescence : None
Solubility : Acids
Magnetism : None
Radioactivity : None