Comparison between Nickel‐Sulfur Fire Assay Te Co‐precipitation and Isotope Dilution with High‐Pressure Asher Acid Digestion for the Determination of Platinum‐Group Elements, Rhenium and Gold

Abstract

The accurate determination of platinum‐group elements (PGE), rhenium and gold is important in both fundamental research and ore deposit studies. Questions have been raised by some authors as to whether the nickel‐sulfur fire assay technique (NiS‐FA) efficiently collects all the PGE. On the other hand, most isotope dilution (ID) techniques can only treat small test portion masses (2 g was used for high‐pressure asher digestion; HPA) and this makes them more vulnerable to nugget effects. We determined PGE concentrations in ten reference materials with the aim of comparing the performance characteristics of the two methods. Both methods determine Ru, Pd, Os, Ir and Pt and we found that there were no significant systematic differences in the recovery. The advantages of NiS‐FA were that: (a) it is capable of determining Rh and Au; (b) the relatively large test portion mass (15 g) reduces the nugget effect and (c) it is faster and less expensive than HPA‐ID. The advantages of HPA‐ID were that: (a) it determined Re and (b) it had low level blanks, lower detection limits and hence better precision in low‐level homogeneous samples. Each technique had advantages and limitations; they should be considered as complementary rather than competing techniques.

Platinum-group elements, S, Se and Cu in highly depleted abyssal peridotites from the Mid-Atlantic Ocean Ridge (ODP Hole 1274A): Influence of hydrothermal and magmatic processes

“…Iridium, Ru, Rh, Pt, Pd and Au were measured in 15 g of sample (< 100 µm mesh) by NiS fire-assay (NiS-FA) with SnCl 2 ·2H 2 O-Te co-precipitation and ICP-MS following the procedure described by Richardson and Burnham (2002) Table 2; the reproducibility for all the elements in better than 3%. PGEAu analyses of three aliquots of the CANMET Certified Reference Material TDB-1 and two aliquots of the GSJ standard JP-1, having PGE concentrations similar to the unknowns, compare well with published values of these materials (Table 2; Shirai et al 2003;Meisel and Moser 2004;Savard et al 2010). …”

Étude du comportement des éléments hautement sidérophiles et chalcophiles dans les gouttelettes sulfurées de MORB /

“…They were determined by High Pressure Asher digestionIsotope Dilution (HPA-ID) at the LabMaTer, UQAC using the techniques described in Savard et al (2010). Results for the OKUM reference material agree with the certificate values.…”

Геохимия Элементов Платиновой Группы В Базальном Платинометально-Медно-Никелевом Оруденении Массива Нюд, Мончегорский Комплекс

“…После дробления и истирания в агатовой планетарной мельнице образцы по скважине 1815 были проанализированы на Cu, Ni, Au и шесть ЭПГ в университете Квебека в Чикутими (УКВЧ) методом ICP-MS после никель-серной пробирной плавки по аналитическому протоколу, изло-женному в работе [7]. Сера анализировалась с использованием высокотемпературного горения с IR-спектрометрическим окончанием и титрованием серы на приборе Horiba 220V S-C в УКВЧ.…”