Wolframite and Beryl (Weight: 1675 g) – Place of discovery: Adun-Cholon Range, Transbaikalia (Zabaykalsky Krai), Far Eastern, Russia — Photo: Kaethe17 · CC BY-SA 4.0
Ferberite
Also known as: Iron wolframate.
The iron end-member of the wolframite series — black monoclinic iron tungstate, a major ore of tungsten.
Intro adapted from Wikipedia (CC BY-SA).
Ferberite is an IMA-recognized mineral species in the tungstate class, with the chemical formula Fe²⁺(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 7.58; typically black or brown; Brownish black to black streak; Submetallic to metallic adamantine luster; refractive index 2.325; optically biaxial.
IMA symbol Feb, grandfathered status — known before the IMA’s founding, named in 1863.
Found in high-temperature hydrothermal veins, greisens, and granitic pegmatites; also residual in alluvial and eluvial deposits.
It is found associated with Scheelite, topaz, fluorite, marcasite, pyrite, hematite, feldspar.
The mineral was named to honor Moritz Rudolph Ferber (1805–1875), amateur mineralogist, Gera, Germany.
Collections: Metals & Native Elements, Collector Favorites.