1. Investigations with the aid of the simplex-lattice method of experimental design and a mathematical formalization permitted an elucidation of the nature of changes in the bending strength, Young's modulus, and true porosity of periclase-spinel ceramic over a range of limiting values of the fractional compositions of the original press powders. 2. Graphs of the distribution of the properties make it possible to choose press powder compositions over a wide range which will ensure a constant level of the properties of the material under test. 3. It was shown that it is necessary to take into account the statistical aspects in research on changes in the strength properties of brittle polycrystalline materials due to variation in the grain structure.