Until very recently, a common view of pegmatite genesis has not been established among a large circle of geologists studying pegmatite deposits. A. E. Fersman's theory of pegmatite formation is still widely popular. The enormous work of A. E. Fersman and his group of colleagues, aimed at collecting materials characterizing the mineral composition of pegmatites in almost all regions of the USSR, played a major positive role, attracting general attention to these deposits and thereby facilitating their rapid industrial development. This group of researchers rightly established that the formation of pegmatites is a very complex process occurring in changing physicochemical conditions and that, in accordance with changes in crystallization conditions, the paragenetic associations of the resulting minerals change. However, a number of fundamental provisions of A. E. Fersman's general theory of pegmatite genesis, as is known, have not been justified. A. E. Fersman's ideas that pegmatites are formed by means of successive crystallization in a closed system, the so-called pegmatite water-fire melt, highly enriched in volatile components, have long been met with objections.
