Analysis of tungsten in low grade ores and geological samples

The determination of tungsten in low grade ores and geological samples is one of the most difficult and challenging tasks. Many of the associated elements, especially molybdenum interfere. These have to be overcome by suitable methods of separation or suppression of the interfering elements. Since the concentrations are low, instrumental methods are preferred over the classical methods. Thus spectrophotometry, fluorometry, atomic absorption spectrometry, atomic emission spectrometry, X-ray fluorescence, neutron activation analysis, electro analytical methods and chromatography are preferred. These are discussed in this review.