Rocks containing 10-140 ng of indium per g are decomposed with hydrofluoric and nitric acids in the presence of 114In. Indium is separated from other constituents by sequential extractions of the bromide, cupferronate, and acetylacetonate, and is then reacted with a substoichiometric amont of EDTA. Excess of indium is removed by acetylacetone extraction and the specific activity of the complexed fraction is determined by counting 114In. Analyses of the U.S.G.S. standard rocks are reported. These show good agreement with previous neutron activation analyses. Repetitive rock analyses indicated an analytical precision of ??4-7%. ?? 1973.
Additional publication details
Determination of indium in rocks by substoichiometric radioisotope dilution analysis