Complex tungsten ores usually refer to ores containing pyrite, antimony, titanium oxide particles, quartz, calcite, sericite, argillaceous material, and cryptic carbon. The separation of crystalline carbon, calcite and Scheelite from complex tungsten ores has always been recognized as one of the difficult problems in ore dressing, and it is also the main reason for this kind of tungsten ore to be difficult to use.

The core component of the magnetron cathode component magnetic control coil requires the uniform distribution of ThO2 particles in the tungsten matrix. At present, the preparation process of the magnetic control coil material powder for magnetron cathode used in foreign countries is to use ammonium paratungstate to burn into the tungsten WO₃ as the raw material, through doping, high temperature sintering, one reduction to doping WO₂ and two times. It was originally doped with W powder. But this method has long working procedure and high manufacturing cost.

The determination of low content of tungsten in ore mainly includes ICP-AES, ICP-MS and visible spectrophotometric method. ICP-AES and ICP-MS instruments are expensive and operating costs are high, and they are not fully popularized at present. The most widely used method is thiocyanate colorimetry. This method is fast, simple, stable, and has wide application scope.

Ammonium paratungstate(APT) is an important tungsten product, mainly used in the manufacture of tungsten trioxide or blue tungsten oxide. At present, the production process of APT products is mainly based on alkali method. Tungsten concentrates or Scheelite Concentrate are extracted and prepared by high pressure alkali boiling and soda pressing. Then, the solution of ammonium tungstate is prepared by solvent extraction or ion exchange method. Finally, the APT product is prepared by evaporation crystallization of ammonium tungstate solution; acid process technology is used. The Scheelite Concentrate is decomposed by hydrochloric acid, dissolved in ammonia, and then evaporated and crystallized to produce APT products.