THE EXISTENCE OF CONTINUOUS SOLID SOLUTIONS IN THE LIVO//3-NAVO//3 SYSTEM AT TEMPERATURES FROM ROOM TEMPERATURE TO THE MELTING POINT OF THE MATERIALS IS PROVEN. IT IS ESTABLISHED THAT THERMAL AND CHEMICAL DEFORMATIONS OF THE CRYSTALS OF THIS SYSTEM HAVE A SHARPLY ANISOTROPIC CHARACTER, I. E. , THE CRYSTAL LATTICE IS MOST INTENSELY DEFORMED ALONG THE B-AXIS IS LESS INTENSELY DEFORMED ALONG THE A-AXIS, WHILE THE SMALLEST DEFORMATIONS ARE OBSERVED ALONG THE C-AXIS. THE ANISOTROPY OF THERMAL AND CHEMICAL DEFORMATIONS AGREES WITH THE SPECIAL FEATURES OF THE CRYSTAL STRUCTURE. AT ROOM TEMPERATURE ON THE GRAPHS OF THE DEPENDENCE OF BREAK IN THE CURVES IS OBSERVED AT X = 1. DURING HEATING OF THE CRYSTALS THIS DEPENDENCE APPROACHES A LINEAR ONE, WHICH MAY BE ATTRIBUTABLE TO DISORDERING IN THE CATION SUBLATTICE. IN RUSSIAN.