Spectrophotometric determination of niobium in rocks
After acid decomposition and evaporation to volatilize silica, samples containing 0.5 6 μg Nb are fused with pyrosulfate and dissolved in hydrochloric acid tartaric acid. Niobium is separated by thiocyanate extraction with amyl alcohol and back-extracting from the organic solvent with dilute hydrofluoric acid. Niobium is reacted with 4-(2-pyridylazo)-resorcinol to obtain a colored species. Analytical error, estimated from replicate analyses of eight U.S. Geological Survey standard rocks, ranges from 2.9 to 6.4 percent at the 1 27 μg/g Nb level.
Citation Information
Publication Year | 1974 |
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Title | Spectrophotometric determination of niobium in rocks |
Authors | L. Paul Greenland, E. Y. Campbell |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Journal of Research of the U.S. Geological Survey |
Index ID | 70232450 |
Record Source | USGS Publications Warehouse |