Platinum ores analyses

Native platinum frequently contains traces of nickel, as evidenced by the spectrochemical examination of specimens from Russia, Spain, and America. A sample from Kitlim,1 for example, contained 0-1 per cent, of nickel or more.8 Only one previous analysis of platinum appears to have been recorded, containing nickel, namely, a magnetic platinum from Nizhne-Tagilsk, in which 0-75 per cent, of nickel was present. Platinum ores rich in iron yield the most intense nickel spectrum. 

As an example of modeling a fluid in redox disequilibrium, we use an analysis, slightly simplified from Nordstrom et al. (1992), of a groundwater sampled near the Morro do Ferro ore district in Brazil (Table 7.2). There are three measures of oxidation state in the analysis the Eh value determined by platinum electrode, the dissolved oxygen content, and the distribution of iron between ferrous and ferric species. 

Leidie A process for extracting the platinum metals from their ores by fusion with sodium peroxide, followed by a complex separation process. Developed by A. Quennessen, a leading French manufacturer of platinum in the 19th century, and E. Leidie. The process is still used for extracting precious metals, and in chemical analysis. 

Complete and trustworthy analyses of ores, etc., containing platinum metals are not easy to effect. They require on the part of the analyst considerable skill and expert knowledge of the eccentricities of the metals concerned. In the present chapter the more important reactions of the metals are outlined, together with the most usual methods of analysis.1... 

Although platinum was introduced to Europe in the mid-18th century, it was first made commercially available in large quantities and in malleable form in 1805 by the English chemist William Hyde Wollaston. Previous attempts at consistently producing malleable metal were hindered by chemical purification techniques that gave platinum contaminated with deleterious metallic impurities. Richard KnighPs improved process of 1800 was carried out on a suitable sample of crude ore, and analysis of the purified platinum by spark source mass spectrometry (SSMS) indicates an impurity level of about 6%. Reconstruction of Wollaston s purification procedures, coupled with SSMS analysis, indicates that his product was over 98% pure. His superior chemical purification techniques, coupled with improvements in the powder consolidation method, explain Wollastons success. 

Steirmes E. Determinahon of rhodium in platinum bearing ores by neutron activation analysis. Radiochemical and Radioanal)rtical Letters 1975 21 233-239. 

Nowinski, P., and Hodge,V. (1994). Evaluation of ICP-MS/Microwave oven preparation for the rapid analysis of ore samples for gold and the platinum-group metals. At. Spectrosc. 15(3), 109. 

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