ИСТИНА

Some of exciting recent developments in the field of mineralogical crystallography are considered. The crystal chemical phenomena (e.g. ionic ordering, polyhedral stacking variations, microtwinning etc.) which accompany the formation of real structures, are discussed on the basis of structural studies of a large group of minerals. The new approaches used for their investigation allowed extending the scientific ideas connected with: the composition and structure of deep geospheres, structural classification of minerals, forms of concentration of chemical elements in the Earth’s crust, further development of modular theory and other problems of modern structural mineralogy.