The results of a detailed study of the mineral and chemical composition, geothermobarometry, and U-Pb isotope dating of zircon of high-aluminous sapphirine-bearing crystals of shales associated with biotite-garnet-sillimanite gneisses, hypersthene-two feldspar and high-potassium hypersthene orthogneisses, Ti-rich and subalkaline …