LAUSR

Abstract The pyrosynthesis of gold chalcogenides AuX (AuTe0.7Se0.2S0.1), AuX2 (AuTe1.8Se0.2–AuTe1.8Se0.1S0.1) and Au3X10 (Au3Te6Se3S–Au3Te6Se2.5S1.5) was performed from a mixture of elemental substances taken in the atomic ratios X/Au (X = Σ(Te + Se + S)) of AuTe0.666Se0.167S0.167 (X/Au = 1), AuTeSe0.5S0.5 (X/Au = 2), AuTe2Se1.125S0.375, AuTe2Se0.75S0.75 (X/Au = 3.5) and AuTe2.5SeS0.5 (X/Au = 4). Optical and scanning electron microscopy, electron microprobe analysis, X-ray powder diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy were applied to characterize the samples. It was established that Au chalcogenides of composition AuX2 were analogous to mineral calaverite (AuTe2), Au3X10 phases were close to S-bearing mineral maletoyvayamite and the AuX substance seemed to be a synthetic analog of a phase Au0.99–1.00Te0.70–0.71Se0.25–0.27S0.03–0.06 found in the Gaching area of the Maletoivayam ore field (Central Kamchatka volcanic belt). The results on complex Au chalcogenides in the quaternary Au–Te–Se–S system are of interest for chemistry, mineralogy and geochemistry of Au, and potential applications in materials science.