Scheelite is a calcium tungstate mineral with the chemical formula CaWO4. It is an important ore of tungsten. Well-formed crystals are sought by collectors and are occasionally fashioned into gemstones when suitably free of flaws. Scheelite has been synthesized via 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 that those with barium platinocyanide; the latter chemical allowed Röntgen to discover X-rays in early November 1895.

 

Scheelite beneficiation is based on flotation process.

Scheelite flotation generally consists of sulfide ore flotation, tungsten roughing and selection.

Principle process of sulfide ore flotation is similar to common sulfide ore flotation concentrators, the difference is the different component of lead, zinc, bismuth, copper and pyrite.

Sodium carbonate and sodium silicate are generally used as modifiers in scheelite roughing, flotation with fatty acids collector, some concentrators use chelate collectors.

Coarse-grained scheelite concentration technology currently consists of two categories, one is heating selection, the other one is normal flotation.

Heating selection is commonly uesd in the separation of scheelite and calcium gangue ores; normal flotation is commonly used in the separation of scheelite and siliceous gangue ores.

 

Process of scheelite recovery from tailings 

The new collector FX, low sodium silicate contents composite chemicals, column - machine combined process.

Indicators in 2010: When the WO3 containing of ore (molybdenum tailings) is averagely  0.06%-0.1%, the tailings grade is about 0.012%, the recovery is greater than 75%, WO3 containing of concentrate is 40%.