Gold solubility in supercritical hydrothermal brines measured in synthetic fluid inclusions

Science

Volumn 284, Issue 5423, 1999, Pages 2159-2163

  Loucks, Robert R ^a   Mavrogenes, John A ^a  

^a AUSTRALIAN NATIONAL UNIVERSITY   (Australia)

Author keywords

[No Author keywords available]

Indexed keywords

GOLD; HYDROGEN SULFIDE; IRON DERIVATIVE; MAGNETITE; SILICON DIOXIDE;

FLUID INCLUSION; GOLD; HYDROTHERMAL FLUID; SOLUBILITY;

ARTICLE; CHEMICAL REACTION KINETICS; EXPERIMENTAL MODEL; MASS SPECTROMETRY; MATHEMATICAL ANALYSIS; PRESSURE; PRIORITY JOURNAL; REACTION ANALYSIS; SOLUBILITY; TEMPERATURE; THERMODYNAMICS;

EID: 0033603395     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.284.5423.2159     Document Type: Article

References (57)

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8. 2. The ice plus an annulus of quartz was laser-ablated and analyzed by ICPMS to simulate ablation and analysis of sealed fluid inclusions. Replicate analyses gave a mean (± 1 SD) U/Th = 5.8 [± 0.2), Au = 105 (± 11) ppm relative to Th, and Au = 107 (± 13) ppm relative to U as the internal standard. The 10 Au determinations gave a pooled mean of 106 ± 9 ppm Au at the 95% confidence limit From the pseudoinclusion tests, we conclude that (i) the analytical result 106 ± 9 ppm agrees with the nominal 103 ppm Au weighed into the standard solution, so no matrix-related bias is evident between the ablated glass standard and the ablated quartz + standard fluid, and (ii) in submicrogram-size samples, our analytical precision for Au by this U-Th dual-intemal-standard procedure is ±∼8% of the actual value.
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51. -3(aq). Cyanides and ammines of Ag and Hg also undergo linear-to-tetrahedral transitions as ligand supply increases [R. J. Lancashire, in Comprehensive Coordination Chemistry, F. Wilkinson, R. D. Gillard, J. A. McCleverty, Eds. (Pergamon, Oxford, UK, 1987), vol 5, pp. 775-860; N. N. Greenwood and A. Eamshaw, Chemistry of the Elements (Pergamon, Oxford, UK, 1984)] .
52. -3(aq). Cyanides and ammines of Ag and Hg also undergo linear-to-tetrahedral transitions as ligand supply increases [R. J. Lancashire, in Comprehensive Coordination Chemistry, F. Wilkinson, R. D. Gillard, J. A. McCleverty, Eds. (Pergamon, Oxford, UK, 1987), vol 5, pp. 775-860; N. N. Greenwood and A. Eamshaw, Chemistry of the Elements (Pergamon, Oxford, UK, 1984)] .
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54. - ions.
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57. We thank S. Eggins, W. Hibberson, L. Kinsley, H. O'Neill, M. Shelley, and N. Ware for technical assistance in experimental and analytical aspects of this study and B. L. N. Kennett for supporting development of the analytical facilities. D. Ellis kindly shared his cold-seal laboratory. Comments by A. Berry, I. Campbell, C. Heinrich, S. Kesson, M. Palin, D. Sverjensky, and anonymous reviewers clarified the presentation.