A material consisting mainly of α-Al2O3 and Al4O4C has been prepared by fusion of a mixture of alumina and thermoanthracite. The crystal-optical constants of Al4O4C have been determined: biaxial, negative, oblique attenuation, rhombic system,N g = 1.809,N m = 1.802,N p = 1.779,N g -N p = 0.030,z-,2V = 123°. The analytical refraction index has been found to beN av = 1.796. The phase composition and the structure of various portions of fused blocks and of granules of the fused material based on Al2O3 and C have been investigated. The interval of the ultimate temperatures of stability of the material (1400 – 1500°C) and the nature of phase and structural transformations in a reducing medium at 1500°C have been established. Articles were manufactured from the fused material 2nd tested in steel pouring with the use of gate valves. The nature of the phase and structural transformations of the articles in operation has also been investigated.