General Spectrographic Technique for the Determination of Volatile Trace Elements in Silicates

Abstract

Details are given of a quantitative dc-arc method for the determination of up to 15 volatile elements in trace amounts in silicates. Twenty milligrams of sample are mixed with an equal weight of an alumina-lime buffer containing 0.1% bismuth trioxide as internal standard and the mixture arced as the anode in a graphite cup. Careful control of arcing conditions allowed the determination of common volatile elements in amounts down to 1 ppm and in the case of several rare elements—notably Ag, Au, In, and Tl—down to 0.1 ppm.