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The pyrites belong to the cubic system (m3) with elements of 3L24L33PC symmetry. At the most deposits and ore occurrences, the crystals of pyrite usually are founded in simple forms such as Cube - 100, pentagonal dodecahedron - 210, octahedron - 111, and the combination of them. However, quite often there are the crystals of pyrite in the rhombohedral form with blunt or sharp shape, such crystals are found in metamorphic shales, and near the deposits of metosomatic low-temperature ore. The formation of rhombohedral crystals of pyrites is explained by the degeneration of sixth or twelfth edges and the uneven development of the edges of pentagonal dodecahedron - 210 It can also bound with the position of the crystal relative to the direction of schistosity when rhombohedral of pyrites are oriented by third-order axis perpendicular to the schistosity level, and overgrowth of the crystal pyrite 210 by small plots of 100 edges, in the result that the surface of the edge is curved, and its angle decreases. The formation of the rhombohedral crystals may be explained with the elemental analysis the cell of pyrite. In our opinion, the symmetry has not cubic nature in the crystal but it is trigonal with a the single of third-order axis.