Fire Assay of Carbonate-Containing Oxide Gold Ores

Year 2024, Volume: 1 Issue: 1, 22 - 26, 26.07.2024

Haluk Özden Başaran Ahmet Turan Onuralp Yücel

Abstract

To analyze gold and silver from ores and concentrates; fire assay still remains the only widely excepted technique. The method has three steps including smelting, cupellation and the characterization of precious metals-containing beads. Finding the ideal amounts of acidic flux materials (borax and SiO2) to add to the smelting charge for the fire assay of carbonate gold ores is the aim of this study. Acidic fluxes, quartz (SiO2), sodium borax decahydrate (borax, Na2B4O7∙10H2O), and basic flux sodium carbonate (Na2CO3) were introduced separately and in combination to the charge mixtures containing samples of carbonate gold ore, lead oxide with flour providing as a carbon source, and lead oxide. The quantity of acidic flux additions were adjusted. Following the cupellation process, beads containing gold were produced. Using AAS and ICP, the beads were digested in nitric acid (HNO3) and aqua regia, respectively, to determine the amount of gold present.

Keywords

Carbonate Gold Ore, Cupellation, Fire Assay, Flux Material

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