Determination of Arsenic in Gold by flow injection inductively coupled plasma mass spectrometry with matrix removal by reductive precipitation

Julian Tyson, University of Massachusetts Amherst
Paul Edward Becotte-Haigh, University of Massachusetts Amherst
E R. Denoyer
M W. Hinds

Abstract

Arsenic was determined in gold by flow injection hydride generation inductively coupled plasma-mass spectrometry following a batch mode reductive precipitation removal of the interfering gold matrix. A solution of potassium iodide, L-ascorbic acid, and hydrochloric acid was used as the reluctant. The recovery of gold by precipitation and filtration was 99 ± 3%. The detection limit for arsenic in gold was 55 ng g-1 in the solid. The concentration of arsenic that was determined in the Royal Canadian Mint gold sample FAU-10 was 29.7 μ.g g-1 in the solid; this value was indistinguishable, with 95% confidence, from values determined at the Royal Canadian Mint by graphite furnace atomic absorption spectrometry and by inductively coupled plasma-mass spectrometry. The standard deviation for four replicate determinations of the arsenic in FAU-10 was 0.972 μ.g g-1 in the solid.