Abstrakt
Palladium and platinum tellurides and selenides were experimentally investigated at 400 degrees C. We have synthesized the binary and ternary phases in the systems Pd/Pt-Se-Te and evaluated them by means of Xray powder-diffraction analysis, reflected light and electron microscopy.
The experiments were performed using the evacuated silica-glass tube method. The phase relations were assessed in the system Pd-Se-Te at 400 degrees C.
Miessite (Pd11Te2Se2) forms stable associations with Pd13Te3 and keithconnite (Pd20Te7), keithconnite and palladseite (Pd17Se15). Miessite also coexists with Pd4Se, Pd7Se2, Pd34Se11 and Pd7Se4.
Telluropalladinite coexists with Pd3Te2 and palladseite. Palladseite coexists with Pd3Te2 and kotulskite ss.
Preliminarily experimental results in the Pt-Se-Te system have shown the complete solid solution sudovikovite (PtSe2) - moncheite (PtTe2). A new ternary phase PtSeTe was observed in the system and is being further investigated.
Assessed stable associations should be sought in assemblages with other PGM and known Pd/Pt selenides and tellurides, likely in magmatic Cu-Ni-PGE mineral deposits, associated with mafic and ultramafic igneous rocks, but also at low temperatures formations like selenide vein-type mineralization.