Growth of Tourmaline Crystals (Based on Natural Observations and Experimental Data)

摘要

The method of growth of an individual crystal determines its internal structure, which in turn characterizes the quality of the crystal. This is especially important for crystals of minerals that are used directly in technology. Tourmaline is one such mineral. But tourmaline crystals that meet technical requirements are encountered very rarely in nature. This necessitates the artificial growth of crystals of this mineral with a composition and properties that are specified in advance. For efficient organization of experiments on the growth of tourmaline crystals one must determine two factors: the optimal thermodynamic parameters of the conditions of crystallization, and the characteristic features of the growth of individual crystals. This report focuses on the second topic by presenting a review of investigations conducted on crystal growth of tourmaline. Growth of natural and synthetic tourmaline crystals is shown to proceed by many modes. The wide range of thermodynamic conditions for the crystallization of tourmalines may account for the inhomogeneity of the internal structure of tourmaline crystals. This inhomogeneity is evident in block structure, in coarse or fine mosaic structure, the presence of flat or tubular cavities, and the presence of solid, gas-liquid, and multiphase inclusions. 6 figures, 1 table. (ERA citation 08:036563)