Etude des défauts dans des monocristaux naturels de béryl. II. Etude de croissance

Growth defects in natural single crystals of beryl have been examined by X-ray topography. The distribution and the configuration of the defects: dislocations, channels, growth bands and growth sector boundaries, are related to the development of the crystals in nature. For some Brazilian samples, characteristic stops and starts during their development and dissolution phenomena have revealed similar conditions of growth.