Cadmium Substitution in Miargyrite (AgSbS2) and Related Phases: An Experimental Reconnaissance

I. Kelleher, S. A. T. Redfern and R. A. D. Pattrick
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, UK
Department of Earth Sciences, The University of Manchester, Manchester, M13 9PL, UK

Abstract: An experimental study of cadmium substitution into AgXS2 phases (X = As, Bi, Sb) indicates significant amounts of cadmium can be incorporated in the structure by the mechanism 2Cd ⇌ Ag + X. The limit of substitution of Cd in the high-temperature polymorph of miargyrite, β-AgSbS2 is 6.2 at.%, whereas the low-temperature polymorph, α-AgSbS2, can accommodate at least 12 at.% cadmium. Substitution of Cd into the cubic β-AgSbS2 induces a small monoclinic distortion and the unit cell becomes pseudo-cubic. The α ⇌ β transition in Cd-substituted miargyrites is modified by the solute ions, with both a reduction of Tc and transition smearing evident. Similar effects are also recorded in Cd-substituted AgAsS2 and AgBiS2.

Keywords: cadmium substitution • miargyrite • As • Bi • Sb

Mineralogical Magazine; June 1996 v. 60; no. 400; p. 393-401; DOI: 10.1180/minmag.1996.060.400.01
© 1996, The Mineralogical Society
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