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Determination of lead in rocks by radiometric isotope dilution and substoichiometric extraction

Philip Aruscavage
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Abstract

A rapid procedure is described for the determination of lead in rocks by an isotope-dilution substoichiometric method. After the sample has been digested with acid in the presence of 210 Pb tracer, the lead is separated by dithizone extractions. After the lead has been back-extracted into aqueous solution, it is reacted with a substoichiometric amount of EDTA. Excess of unreacted lead is removed by extraction with dithizone in carbon tetrachloride, and the specific activity of the aqueous complex is determined by counting 210 Pb. The standard deviation of the method is less than 10 % for replicate determinations of lead in several U.S. Geological Survey standard rocks. The agreement with literature values indicates that the method is accurate.

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Philip Aruscavage. 1976. Determination of lead in rocks by radiometric isotope dilution and substoichiometric extraction. https://doi.org/10.1016/s0003-2670(01)84612-2

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