Evaluation of mercury content in amalgams from Munhena mine, Mozambique

• Published in: Journal of cleaner production Vol. 84; pp. 783 - 785
• Main Authors: Kiefer, Adam M., Drace, Kevin, Gottlieb, Samuel, Coursey, Stephen, Veiga, Marcello M., da Cruz Marrumbe, Prudêncio Noélio, Jose Chapo, Micaela Arlete
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2014
• Subjects: Amalgams; Artisanal and small-scale gold mining; Combustion; Gold; Gold amalgamation; Mercury (metal); Miners; Mines; Mining; Mozambique; Phase diagrams; Mozambique; Artisanal and small-scale gold mining; Gold amalgamation; Mozambique
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2013.09.039

Artisanal gold mining amalgams from the Munhena mine in Manica province, Mozambique were burned under laboratory conditions to determine the ratio of mercury to sponge gold. When compared to established phase diagrams of the mercury–gold alloy, the results indicate that all miners actually form a mixture of amalgam and excess mercury. The variability in mass percentage of mercury in each artisanal amalgam is indicative of the techniques used by individual miners to form their amalgam. Removal of excess mercury prior to the burning process will greatly reduce the amount of mercury evolved during the mining process. •Determination of the ratio of mercury to sponge gold in Mozambican ASGM amalgams.•Based on phase diagrams, ASGM amalgams contain excess mercury.•Excess mercury can/should be removed prior to burning the amalgam.•Suggestions for simple technology to remove excess mercury from ASGM amalgam.