Quantitative chemical analyses of rocks by X-ray fluorescence spectrometry using a mixed alkali flux (Li_2B_4O_7 : LiBO_2=7 : 3)

A systematic XRF analytical routine for major and trace elements of silicate rocks using a mixed alkali flux (Li_2B_4O_7 : LiBO_2= 7 : 3,Spectromelt A12) has been made with the Rigaku RIX3000 introduced in the Center of Instrumental Analysis, Yamaguchi University. With usage of the Spectromelt A12 (Merck), a homogeneous glass bead could be made even in an infusible quartz-rich rock. In order to make calibration curves, we used 32 geochemical standard samples issued by Geological Survey of Japan, U.S. Geological Survey, Korean Institute of Energy and Resources and S. Africa Bureau of Standards, and the analytical results were a fairly good in comparison with the recommended values for a wide variety of rocks ranging from siliceous to ultramafic ones. Repeated analyses of JB-1a and JG-1a using the calibration curves proved that the analytical system is very well also in the reproducibility. Using this method (named UME5), major and trace element analyses were possible using one single glass bead.