Publication Date:
2018
Description:
〈div data-abstract-type="normal"〉〈p〉Structural data for weishanite, an alloy of Au, Ag and Hg, were collected for the first time from a crystal from the Keystone Mine, Colorado, USA. The structure was solved in the space group 〈span〉P〈/span〉6〈span〉3〈/span〉/〈span〉mmc〈/span〉 with the unit cell 〈span〉a〈/span〉 = 2.9348(8) and 〈span〉c〈/span〉 = 4.8215(18) Å] and refined to 〈span〉R〈/span〉 = 0.0299 for 40 observed reflections [4σ(〈span〉F〈/span〉) level] and four parameters and to 〈span〉R〈/span〉 = 0.0356 for all 47 independent reflections. The weishanite structure can be considered a derivative of the zinc structure, with Au, Ag and Hg disordered in the same structural position. On this basis, we suggest that the formula is normalized to 1 atom with 〈span〉Z〈/span〉 = 2, leading, for the sample investigated, to Au〈span〉0.41〈/span〉Ag〈span〉0.31〈/span〉Hg〈span〉0.28〈/span〉 (electron microprobe data). Accordingly, weishanite can be considered the Au-rich isotype of schachnerite. A comparison with other Au/Ag-Hg alloys is presented together with a critical discussion about the nomenclature rules to be applied to alloys and simple metals.〈/p〉〈/div〉
Print ISSN:
0026-461X
Electronic ISSN:
1471-8022
Topics:
Geosciences
