Raman spectroscopy characterisation of synthetic platinum-group minerals (PGM) in the Pd–Sn–Te and Pd–Pb–Te ternary systems

Abstract: The identification of minerals that occur as tiny and rare phases such as most of the natural platinum-group minerals (PGM) is a challenging target. The main reason for that resides in their size (generally less than 10 micrometres) and mode of occurrence (i.e. polyphasic aggregates) that make problematic the identification by standard X-ray diffraction methods. In this contribution we have applied the Raman spectroscopy to synthetic PGM in the ternary systems Pd–Sn–Te and Pd–Pb–Te. Some of the analyzed PGM show characteristic Raman bands and the following PGM can be distinguished using the Raman spectroscopy: merenskyite, kotulskite, kojonenite, pašavaite and Pd3Te2. Other PGM in the ternary Pd–Sn–Te and Pd–Pb–Te systems cannot be identified using this technique. These results demonstrate that Raman spectroscopy can be considered as an innovative and complementary methodology with a potential to identify and to better characterize the PGM. Key-words: platinum group minerals (PGM); tellurides; Pd–Sn–Te system; Pd–Pb–Te system; Raman spectra