Conditions of formation of the diaspore in the primary fluid inclusions in corundum of the Sutara deposit (Russian Far East)

The data on the composition of primary fluid inclusions in corundum of Sutara deposit were first obtained by Raman spectroscopy using a Horiba LABRAM HR 800 spectrometer. Their primary fluid inclusions contained daughter diaspore crystals, which had not been previously detected in the inclusions of Sutara corundums (Jewish Autonomous Region, Russian Far East). Using Selector software based on thermodynamic calculations reaction: we found that the formation diaspore at CO2 fluid occurred at a temperature 305 °С and did not depend on pressure. In the H2O-CO2 fluid, the balance of corundum - diaspore shifted in the high temperature section and detected dependence on pressure. Thus, for the known temperature and the composition of H2O-CO2 fluid the diaspore inclusion in corundum may serve as geothermometer.