A method for the determination of silver in ores and mineral products by atomic-absorption spectroscopy

Abstract

An atomic-absorption spectroscopic method for the determination of silver in some ores and mineral products is reported. The effects of sorption of silver on the container walls, cleanliness of equipment, stability of standards and sample solutions, interference from silicate ions and background absorption have been studied.

The sample is treated with mixed acids (including hydrofluoric) and evaporated to dryness; the acid extract of the residue is then made strongly ammoniacal and the solution nebulised. Recoveries are, on average, about 10 per cent. higher than those obtained by using fire assay. Silver values obtained by the proposed procedure are almost quantitative for sulphide ores, but with other ores they are about 3 per cent. low, unless the final residue is re-examined.