Silicate Analysis—a Glance Backward and a Look Forward

Abstract

Silicate rock analysis is in a state of flux. Methods are changing rapidly in response to shifting requirements of geologists and geochemists. V. M. Goldschmidt’s geochemical investigations in the 1930’s established the utility of spectrography for quantitatively determining trace elements in rocks. This technique remains the best instrumental method for yielding the maximum qualitative and quantitative information with the minimum effort. This success was followed by an ever increasing array of instrumental methods. The more significant include spectrophotometry, flame photometry, polarography, x-ray fluorescence, chromatography, atomic absorption, and neutron activation. Since World War II emphasis has been on the development of rapid methods, especially for the major and minor elements and on evermore sensitive methods for the trace elements. New field methods for geochemical prospecting and remote methods for extraterrestrial studies have been developed. Computer techniques for analyzing and recording experimental data are being developed, as many instruments produce much more information than can be assimilated by older calculating and recording methods.