For the community in California, see Scheelite, California.
Scheelite
General
Category
Tungstate mineral
Formula (repeating unit)
CaWO4
IMA symbol
Sch[1]
Strunz classification
7.GA.05
Crystal system
Tetragonal
Crystal class
Dipyramidal (4/m) H-M symbol: (4/m)
Space group
I41/a
Unit cell
a = 5.2429(3), Å c = 11.3737(6) Å; Z = 4
Identification
Color
Colorless, white, gray, dark brown, brown, tan, pale yellow, yellow-orange, golden yellow, pale shades of orange, red, green, etc.; colorless in transmitted light and may be compositionally color zoned
Crystal habit
Pseudo-octahedra, massive, columnar, granular
Twinning
Common, penetration and contact twins, composition plane {110} or {001}
Cleavage
On {101}, distinct; on {112}, interrupted; on {001}, indistinct
Fracture
Subconchoidal to uneven
Tenacity
Brittle
Mohs scale hardness
4.5–5
Luster
Vitreous to adamantine
Streak
White
Diaphaneity
Transparent to opaque
Specific gravity
5.9–6.1
Optical properties
Uniaxial (+)
Refractive index
nω = 1.918–1.921, nε = 1.935–1.938
Birefringence
δ = 0.017
Pleochroism
Definite dichoric in yellow (yellow to orange-brown)
Fusibility
With difficulty
Solubility
Soluble in alkalis. Insoluble in acids
Other characteristics
Fluorescence under short-wave UV is bright blue, bluish white to yellow. Specimens with more molybdenum tend to fluoresce white to yellow, similar to powellite. Occasionally fluoresces red under mid-wave UV.
References
[2][3][4][5]
Scheelite is a calcium tungstate mineral with the chemical formula CaWO4. It is an important ore of tungsten (wolfram). Scheelite is originally named after Swedish chemist Carl Wilhelm Scheele (1742–1786). Well-formed crystals are sought by collectors and are occasionally fashioned into gemstones when suitably free of flaws. Scheelite has been synthesized using the Czochralski process; the material produced may be used to imitate diamond, as a scintillator, or as a solid-state lasing medium. It was also used in radium paint in the same fashion as was zinc sulphide, and Thomas Edison invented a fluoroscope with a calcium tungstate-coated screen, making the images six times brighter than those with barium platinocyanide; the latter chemical allowed Röntgen to discover X-rays in early November 1895. Note, the semi-precious stone marketed as 'blue scheelite' is actually a rock type consisting mostly of calcite and dolomite, with occasional traces of yellow-orange scheelite.
Scheelite is a calcium tungstate mineral with the chemical formula CaWO4. It is an important ore of tungsten (wolfram). Scheelite is originally named...
1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternative name. The...
(29 km) road that runs from the Nevada Scheelite Mine to U.S. Route 50. The road is also known as Nevada Scheelite Mine Road. Prior to the 1976 mass renumbering...
phosphate, and copper, as well as mineral reserves like gold, emeralds, scheelite, magnetite, vermiculite, silicon, and mica. Commodities such as black...
economically extracted. The ore minerals of tungsten include wolframite, scheelite, and ferberite. Tungsten is used for making many alloys. Tungsten ore...
mineral between ferberite (Fe2+ rich) and hübnerite (Mn2+ rich). Along with scheelite, the wolframite series are the most important tungsten ore minerals. Wolframite...
of the Blowpipe (1827). Cronstedt discovered the mineral now known as scheelite in 1751 at Bispberg Klack, later obtaining samples from the Kuhschacht...
diamond simulant. Due to the scarcity of natural gem-quality scheelite, synthetic scheelite is much more likely to simulate it than diamond. A similar case...
(210 mi) southwest of the capital, Vienna. Mittersill is the largest scheelite deposit in Europe, having in 2010 estimated reserves of 6.1 million tonnes...
color-specific fluorescence. For instance, under short-wave UV light, scheelite, a tungsten ore, fluoresces a bright sky-blue, and willemite, a minor...
the orange fluorescence of zircon. Powellite (calcium molybdate) and scheelite (calcium tungstate) fluoresce intrinsically in yellow and blue, respectively...
ratios; as a result, it is considered to be crystallographically similar to scheelite (CaWO4). Wulfenite is classed by a pyramidal-hemihedral (tetragonal dipyramidal)...
Scheele discovered that a new acid, tungstic acid, could be made from scheelite (at the time named tungsten). Scheele and Torbern Bergman suggested that...
Monazite also shares many structural similarities with; zircon, xenotime, scheelite, anhydrite, barite, and rhabdophane. Monazite sand from Brazil was first...
manufacturers, and also transits through Sète. It can be extracted from scheelite, for example at Salau in the Ariège region of France. The major talc deposit...
minerals include pyrite, chalcopyrite, quartz, anhydrite, fluorite, and scheelite. Important deposits include the disseminated porphyry molybdenum deposits...
tin and tungsten in the form of wolframite, cassiterite, stannite and scheelite. These are the leading source of copper ore. Porphyry copper deposits...
with alkalis to produce soluble tungstates. Alternatively, CaWO4, or scheelite, is allowed to react with HCl to produce tungstic acid, which decomposes...
and a specific gravity of 4.25. It forms a solid solution series with scheelite (calcium tungstate, CaWO4). It has refractive index values of nω=1.974...
scheelite and pyrite. The production of the mineral is thought to be from oxidative alteration of sulfides: a reaction between dolomite and scheelite...
37: 679–690. Howard, W.R. (2016). "Surveys of recovered Visible Gold, scheelite & metallic mineral grains and Heavy Minerals in bulk stream silts 2013–2015...
Another English translation was published by Dr Leonard Dobbin, in 1931. Scheelite Scheele's Green Pharmacist Pharmacy Pneumatic chemistry List of independent...
aragonite, opal, apatite, chalcedony, corundum (ruby and sapphire), scheelite, selenite, smithsonite, sphalerite, sodalite. The first person to observe...
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