Crystal chemical features of vein quartz from the Saralinsk deposit as an indicator of the productivity of gold mineralization (Kuznetsk Alatau, Russia)

Quartz samples from gold-bearing veins of the Saralinsk deposit were studie d by means of optical and high-voltage high-resolution transparent electron microscopy (TEM), chemical analysis, infrared (IR) spectroscopy, thermogra vimetry, and X-ray analysis. Samples were selected from two quartz modifica tions different by structural-textural and physical-chemical characteristic s. The Qu I samples were of transparent dark-gray quartz and samples Qu TI were of opaque milk-white quartz associated with ore minerals and native go ld. principal differences in the crystal chemical state of two quartz gener ations were shown. The sample Qu I contains more gold and silver, as well a s structurally bonded water. Crystal lattice parameters of Qu I differ from those of chemically pure SiO2. Crystalline clusters of gold several tens o f angstroms in size were fixed in annealed samples. Gold enters into quartz in the shape of a complex water-impurity defects [2SiO(3)-OH2-Au2FeO4] and forms a solid interstitial solution in SiO2.