Conditions for crystallization of various forms of chrysoberyl crystal growth

On the basis of the experimental data on chrysoberyl crystal growth, the conditions have been revealed, under which growth twinning is impossible. The established dependence of the dominance of some growth forms over others under various conditions of crystallization medium permitted elucidation of the causes of crystal twinning. The latter is shown to depend primarily on beryllium and aluminium concentrations in mineral forming impurities. The criteria of the origin and growth of well formed colored individuals have been found, which are of great interest for their practical use.