wolframite


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Related to wolframite: scheelite, cassiterite, wulfenite

wolframite

(wo͝ol`frəmīt'), reddish-brown to grayish-black lustrous mineral, a tungstate of iron and manganese, (Fe,Mn)Wo4, occurring in crystals of the monoclinic system. It is the chief ore of the metal tungsten. Widely distributed in nature, it is mined in England, Portugal, Bolivia, Myanmar and the Malay Peninsula, S China, Australia, and W United States.
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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Wolframite

 

a mineral, formula (Fe, Mn) [WO4]; belongs to the isomorphous series whose terminal members are huebnerite, Mn[WO4], and ferberite, Fe[WO4]. It contains 74-76 percent WO3. Characteristic admixtures are MgO, Ta2O5, Nb2O5, ThO2, and Sc2O3. The content of niobium and tantalum is associated with an isomorphous impurity, but more often with very fine inclusions of minerals of the columbite group. It crystallizes in a monoclinic system. Laminar, thick-tabular, prismatic crystals, minute laminar grains, and coarse-grained aggregates are common. Wolframite is brownish black, huebnerite is reddish, and ferberite is black. The luster is bright to diamondlike. Hardness on the mineralogical scale, 5-5.5; density, 6,700 kg/m3 for huebnerite, and 7,500 kg/m3 for ferberite. Wolframite is found in greisens and quartz veins associated with muscovite, topaz, fluorite, beryl, bismuthine, cassiterite, molybdenite, arsenopyrite and, rarely, antimonite. It is sometimes replaced by scheelite. In an oxidation zone, wolframite is partly replaced by tungsten ochers (tungstite) and ferritungstite.

Wolframite is the main ore mineral from which tungsten is obtained. When it contains large amounts of Sc and Ta, they can be extracted as by-products.

REFERENCE

Barabanov, V. F. Mineralogiia vol’framitovykh mestorozhdenii Vostochnogo Zabaikal’ia [vol. 1]. Leningrad, 1961.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

wolframite

[′wu̇l·frə‚mīt]
(mineralogy)
(Fe,Mn)WO4 A brownish- or grayish-black mineral occurring in short monoclinic, prismatic, bladed crystals; the most important ore of tungsten. Also known as tobacco jack; wolfram; wolframine.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
240 & 249b) (referring to Dodd-Frank's definition of conflict minerals, which includes gold, casiterite, wolframite, and coltan).
Ore minerals in the deposit consist of scheelite, minor wolframite, and molybdenite.
Violence and atrocities continue where armed groups profit from the sale of gold, coltan, wolframite and cassiterite mined by locals under inhumane conditions.
Yet, besides these useful attributes lies the fact that the coltan trade based in eastern DRCongo is one of the various mineral trades--including gold, cassiterite, wolframite and diamonds--whose associated million-dollar illegal trafficking has served to brutally destabilise eastern Congo and fuel the ongoing conflict in which an estimated 5 million deaths have occurred since 1996.
Predominantly this deposit is composed of quartz, wolframite, scheelite, apatite and arsenopyrite with minor amounts of bismuth, bismuth tellurides and sulfides, pyrrhotite, chalcopyrite and sphalerite; it formed from late-stage fluids derived from the granite.
Huge wolframite mineral deposits, the main ore that provides the metal tungsten, were found at Hemerdon in 1916 and mined until 1944.
The deposits are made up of quartz containing casiterite and wolframite, with a usable content of 0.4%.
He then named his original mineral wolframite, after the German wolfrahm.
Tourmalinization of wall rock and the occurrence of scheelite as an ore mineral, along with wolframite, is restricted to Balda.
It also has abundant reserves of silver, copper, zinc, lead, uranium, wolframite, tungsten and molybdenum.
Conventionally, pure [WO.sub.3] is produced through a multi-step alkaline-based leaching process of either scheelite or wolframite concentrates.
Normally they don't bother people unless they have Tunsten or Wolframite. That's what they like to eat.