THE CRYSTAL CHEMISTRY OF COSALITE BASED ON NEW ELECTRON-MICROPROBE DATA AND SINGLE-CRYSTAL DETERMINATIONS OF THE STRUCTURE

Crystal-structure refinements done on six samples of cosalite with different types and degrees of copper and silver substitutions, as well as electron-microprobe studies of 33 different samples of cosalite, both enlarged and clarified the spectrum of cation substitutions and the crystal chemistry of this species. The Ag + Bi ↔ 2Pb scheme of substitution acts at the structural site null Me 1. The 2(Cu + Ag) ↔ Pb scheme is a result of two combined...