Tzankova, N. 2007. Variability of rhombododecahedral garnet crystals from metamorphic rocks in the frame of the Sakar Pluton, SE Bulgaria. – Comptes rendus de l’Academie bulgare des Sciences, 60, 2, 155-158.
Deviations from the ideal rhombododecahedron are observed in garnets in metamorphic rocks from the frame of the Sakar pluton. They are presented in elongation of the crystals along one of the axes G4 or G3, around which the elongated in the same direction quadrangular rhombohedral or hexahedral faces are developed. The point group of the visual symmetry of the crystals is interpreted in terms of the Curie symmetry-dissymmetry principle. The influence of the orientated pressure, active perpendicular to one of the axes of the symmetry is supposed for the main factor, which has provoked the anisotropic conditions of the garnet crystal growth.
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