Original paper

Exploratory studies of the solubility of minor elements in tetrahedrite. VI. Zinc and the combined zinc-mercury and iron-mercury substitutions

Karup-Mø ller, Sven; Makovicky, Emil

Abstract

Twenty-six tetrahedrite charges were weighed out in the system Cu12 Sb4 S13 – Cu14 Sb4 S13 – Cu10 Zn2 Sb4 S13, analysed by means of electron microprobe and their a parameter was determined by X-ray diffraction using a GuinierHÄgg camera. For Cu-poor tetrahedrite a(Å) = 0.0293 Zn (p. f. u.) + 10.324 and for Cu-rich tetrahedrite a (Å) = –0.0319 Zn (p. f. u.) + 10.448. Up to ~ 0.6 Zn atoms p. f. u., low-temperature exsolution into Cu-poor and Cu-rich tetrahedrite takes place. Twenty-one charges that combine Zn and Hg substitution and several orientational charges with Fe – Hg substitution confirm the miscibility of these elements in tetrahedral sites of the structure and the linearity of unit cell parameter changes caused by these substitutions.

Keywords

zn-bearing tetrahedritezn-hg bearing tetrahedritecubic unit cell parameter