Neutron activation determination of noble metals in samples of terrestrial and cosmic origin using microfire assay concentration

Abstract

The effects of various factors (composition of mixture, relationship between the mass of mixture and sample, value of the Ni:S ratio, fusion time, and temperature) on the conditions of the fire assay concentration of the noble metals with nickel sulfide were investigated, and a method proposed for their quantitative separation from different geological matrices with a neutron activation determination for up to 10^–1–10^–3 ppb. The proposed method is used to analyse geological samples, i.e., ores, stones, iron meteorites, chromites, soil and lunar rocks.