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USGS · 70011071

Semiquantitative spectrographic method for analysis of minerals, rocks, and ores

C. L. Waring·C. S. Annell
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Abstract

The quantity and complex nature of materials received for analysis in the spectrographic laboratories of the U. S. Geological Survey have emphasized the need for a spectrographic method to determine a maximum number of elements in a limited time with a reasonable degree of accuracy. The semiquantitative method described determines 68 elements in one arcing of a 10-mg. sample. The method has been used to complete 245,000 determinations during a 3-year period. Each determination is reported as a concentration range or bracket (0.001 to 0.01, 0.01 to 0.1%, etc.). A chemical check of 500 such determinations showed 92% in agreement; the remaining 8% agreed to within one bracket. The method requires a minimum of sample handling, thus reducing the chances of contamination, detects low concentrations of elements, and is rapid. Analyses have been completed on a wide variety of materials.

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C. L. Waring, C. S. Annell. 2002-05-01. Semiquantitative spectrographic method for analysis of minerals, rocks, and ores. https://doi.org/10.1021/ac60080a008

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