Determination of thorium by fluorescent x-ray spectrometry

I. Adler; J. M. Axelrod

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USGS · 70010984

Determination of thorium by fluorescent x-ray spectrometry

I. Adler·J. M. Axelrod

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Abstract

A fluorescent x-ray spectrographic method for the determination of thoria in rock samples uses thallium as an internal standard. Measurements are made with a two-channel spectrometer equipped with quartz (d = 1.817 A.) analyzing crystals. Particle-size effects are minimized by grinding the sample components with a mixture of silicon carbide and aluminum and then briquetting. Analyses of 17 samples showed that for the 16 samples containing over 0.7% thoria the average error, based on chemical results, is 4.7% and the maximum error, 9.5%. Because of limitations of instrumentation, 0.2% thoria is considered the lower limit of detection. An analysis can be made in about an hour.

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I. Adler, J. M. Axelrod. 1955. Determination of thorium by fluorescent x-ray spectrometry. https://pubs.usgs.gov/publication/70010984

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