Abstract: A review is presented of developments in the determination of precious metals in recent years, with emphasis on applications. The precious metals covered in the review include the six platinum group metals, plus Au and Ag (785 references).

Abstract: A review with many references. Plasma spectrometry is one of the most popular and versatile techniques for the analysis of geological and environmental samples, including rocks and minerals, waters, dust, vegetation, soils, sewage sludges and sediments. Inductively coupled or DC argon plasmas are used as emission sources in ICP- and DCP-atomic emission spectrometry (ICP-AES, DCP-AES); an ICP provides an ion source in ICP-mass spectrometry (ICP-MS). Reviews of the two plasma sources sample introduction systems, and the instrumental and analytical performances of emission and mass spectrometers, demonstrates the superiority of higher-temperature, ICP-based systems. ICP-AES and ICP-MS are characterized by wide linear responses of more than five orders of magnitude. They are rapid and highly cost-effective multi-element techniques which can theoretical determine over 70 elements in <2 mL of sample solution in less than 2 min. In practice such performance is rarely possible because detection limits, and particularly in the case of ICP-AES, spectral interferences, limit the range of elements which may be quantified. Plasma spectrometry is primarily a solution-based technique, and the dissolution step ultimately controls both the range of elements quantifiable and the limits of determination which may be achieved. Limits of quantitative analysis for solid samples are typically in the order of a few µg g-1 for ICP-AES and a few hundred ng g-1 for ICP-MS. However, chemical separation and pre-concentration procedures are described for the rare-earth elements, precious metals and several other elemental groups, which enable determinations to be made at sub ng g-1 levels. The better precision of ICP-AES and the greater sensitivity, near-complete freedom from interferences, and isotopic capabilities of ICP-MS, mean that ICP-AES is best used for major- and minor-element determinations, while ICP-MS is reserved for trace- and ultratrace-element work. Comparisons with atomic absorption x-ray fluorescence and instrumental neutron activation demonstrate that plasma-based techniques compete well with more established instrumental methods. Further developments in sample preparation and presentation procedures, particularly in the area of solid sample analysis, will increase further the potential applications of plasma spectrometry in the earth sciences.

Abstract: A review with 145 references on the modern instrumental anal. of multicomponent precious metal elements with emphasis on the anal. methods for multicomponent precious metal elements including ICP-MS, NAA, ICP-AES, AAS, HPLC, spectrophotometric analysis, FIA, and electroanalysis. Some suggestions on the development of trace precious metal anal. were provided.