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USGS · 70162699

Spectrophotometric determination of tungsten in rocks by using zinc-dithiol

Philip Aruscavage·Esma Campbell
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Abstract

Tungsten is determined in 11 USGS standard rocks by a spectrophotometric procedure that measures the absorbance of the tungsten-dithiol complex. The results are compared with those obtained by other methods. After the samples are dissolved in HClO 4 and HF, the tungsten-dithiol complex is extracted into isoamyl acetate and then back-extracted into isoamyl acetate. The determination of 0.1 part per million in a 500-mg sample can be made routinely.

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Philip Aruscavage, Esma Campbell. 1978. Spectrophotometric determination of tungsten in rocks by using zinc-dithiol. https://pubs.usgs.gov/publication/70162699

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