EMPA, XRD, and Raman Characterization of Ag-Bearing Djurleite from the Lubin Mine, Lower Silesia, Poland

Abstract

The chalcocite group minerals are widely distributed among different hydrothermally affected rocks, the oxidized zone of copper sulfide deposits, or may be even crystalline from supersaturated volcanic gases. Some of the chalcocite group minerals form the main Cu orebodies. Djurleite (Cu31S16) is a rare member of the chalcocite group, with a very complex structure. The physical and chemical similarities between all members of the group make them almost unidentifiable by macroscopic and microscopic methods. In this study, Ag-bearing djurleite from the Kupferschiefer deposits, Lower Silesia, Poland, is characterized by EMPA (Electron Microprobe Analyses), XRD (X-Ray Diffraction), and Raman spectroscopy. Djurleite from the investigated site has the following general, average chemical formula: Cu30.86Ag0.1Fe0.04S16. The Ag content is up to 0.55 wt.%, while Fe is up to 0.19 wt.%. The presence of djurleite confirms a low-temperature (~90 °C), hydrothermal origin of the Cu-Ag deposit in Kupferschiefer, which is consistent with previously studies. Moreover, the authors believe that Ag-rich djurleite may often be mistaken for Ag-rich chalcocite, which used to be one of the main Ag-bearing minerals in the orebody from the Cu-Ag deposit in the Fore-Sudetic Monocline. However, the confirmation of such a statement requires more samples, which should be studied in detail.

Copper-Arsenic-Sulfide Thin-Films from Local Raw Materials Deposited via RF Co-Sputtering for Photovoltaics

“…The GIXRD spectrum of position 17 details a small shift of several peaks to lower 2θ values, which is characteristic of the increase of Cu concentration for these copper sulfide compounds [39,42], and a general decrease of peak intensity, thus indicating reduced crystallinity. Nevertheless, the main phase is still considered to be Cu 31 S 16 [42,43].…”

“…The GIXRD spectrum of position 17 details a small shift of several peaks to lower 2θ values, which is characteristic of the increase of Cu concentration for these copper sulfide compounds [39,42], and a general decrease of peak intensity, thus indicating reduced crystallinity. Nevertheless, the main phase is still considered to be Cu 31 S 16 [42,43]. Moreover, the GIXRD spectrum of position 18 (furthest from the As-S target), shown in Figure S4d in SM, presents no peaks, revealing the complete amorphization of the film.…”

Precursor engineering for soft selective synthesis of phase pure metal-rich digenite (Cu9S5) and djurleite (Cu31S16) nanocrystals and investigation of their photo-switching characteristics

“…40 A detailed literature survey revealed that the djurleite phase is only stable up to 95 ± 3 °C at atmospheric pressure. [41][42][43] Thus, the primary reason behind its formation via SSP 2 is the lower than boiling water decomposition temperature of the complex in OAm. However, an explanation was still required regarding the ultralow decomposition temperature of 2 compared to 1.…”