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USGS · 70011497

Determination of palladium, platinum and rhodium in geologic materials by fire assay and emission spectrography

J. Hapfty·L.B. Riley
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Abstract

A method is described for the determination of palladium down to 4ppb (parts per billion, 10 9 ), platinum down to 10 ppb and rhodium down to 5 ppb in 15 g of sample. Fire-assay techniques are used to preconcentrate the platinum metals into a gold bead, then the bead is dissolved in aqua regia and diluted to volume with 1 M hydrochloric acid. The solution is analysed by optical emission spectrography of the residue from 200 μl of it evaporated on a pair of flat-top graphite electrodes. This method requires much less sample handling than most published methods for these elements. Data are presented for G-1, W-1, and six new standard rocks of the U.S. Geological Survey. The values for palladium in W-1 are in reasonable agreement with previously published data.

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J. Hapfty, L.B. Riley. 1968. Determination of palladium, platinum and rhodium in geologic materials by fire assay and emission spectrography. https://doi.org/10.1016/0039-9140(68)80014-1

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