X-Ray Spectroscopic Determination of Columbium and Tantalum in Rare-Earth Ores

A method is presented in this paper for the analysis of columbium and tantalum in monazite or similar ores. This method involves the use of x-ray spectroscopic techniques employing the latest instrumentation. The intensity of the columbium and tantalum spectra is calculated and related to corresponding zirconium and hafnium spectra as internal standards. These intensity ratios are then converted to concentrations by the use of typical working curves. The lower concentration limit is 0.05 percent for columbium and 0.2 percent for tantalum, and the standard deviation is approximately 5 percent at concentrations of 2 percent of either element. Single determinations can be made in 40 minutes.