The dc spectrochemical method based on the emission of CaF bands has been adapted to the determination of fluorine in standard rocks. The main difficulty of the spectrochemical method, namely, the need to prepare suitable working standards for each sample, was circumvented by using the single addition method. In the excitation step the problem arising from the difference in the volatility of Ca and F, which results in nonuniform supply of these elements to the arc, was overcome by burning the samples in the Stallwood jet. The coefficient of variation for a single determination is about 15%. The results for 10 standard rocks are presented and compared with previously published data.
I. Schoenfeld, "Spectrographic Determination of Fluorine in Standard Rocks," Appl. Spectrosc. 24, 359-361 (1970)