title: Comparison of silver results for canadian reference ores and concentrates and zinc-processing products by acid decomposition, tribenzylamine/chloroform extraction and fire-assay combined with atomic-absorption spectrophotometry.
abstract: The results obtained for silver in Canadian reference ores and concentrates and in zinc-processing products by three atomic-absorption spectrophotometric methods are compared. "Wet chemical" methods based on the decomposition of the sample with mixed acids yield more accurate results than those based on fire-assay collection techniques. A direct acid-decomposition method involving the determination of silver in a 20% v/v hydrochloric acid-1% v/v diethylenetriamine medium is recommended for the determination of approximately 10 mug g or higher levels of silver. A method based on chloroform extraction of the tribenzylamine-silver bromide ion-association complex from 0.08M potassium bromide-2M sulphuric acid is recommended for samples containing < 10 mug of silver per g.
authors.affiliation: Mineral Sciences Laboratories, Canada Centre for Mineral and Energy Technology, Department of Energy, Mines and Resources, Ottawa, Canada.
authors.forename: E M
authors.initials: EM
authors.lastname: Donaldson
authors.forename: E
authors.initials: E
authors.lastname: Mark
authors.forename: M E
authors.initials: ME
authors.lastname: Leaver