Abstract
Procedures of spectrochemical determination of trace elements such as Ba, Cu, Fe, Ga, Li, Mn, Rb, , Sr and Ti contained in plagioclase feldspars are described.
The cathode layer excitation with d.c.arc of 180 volts is used.The standard mixtures correspond-ing to the anorthite contents of 0-100% are prepared by mixing silica, alumina, calcium carbonate and sodium carbonate and the effects of thus prepared matrices on the line intensities of above men-tioned trace elements are studied and corrections are made for these effects.
As the internal standard, palladium, indium and calcium are used.
The effects of matrix compositions were remarkable for Ba, Cu, Li, Mn, Rb, Sr and Ti, while they were negligible for Ga and Fe.
Relative deviations from sixfold replicate analyses were about 15% for Ba, Cu, Ga, Mn and Ti, 10 % for Fe and Rb, 5% for Li and 3% for Sr.
A Mannkopff type glass spectrograph is used for the determination of Ba, Li, Rb and Sr and a medium quartz spectrograph for other elements.The standard samples G-1 and W-1 are analyzed for Ba, Li, Rb and Sr.
