Yegorovite

Yegorovite, ([Na4[Si4O8(OH)4]·7H2O]) is a silicate mineral found in a hyperalkaline pegmatite in the Lovozero Pluton at Mt. Kedykverpakhk in the Kola Peninsula of Russia. It was named in memory of Russian crystallographer Yurii Kavdievich Yegorov-Tismenko, and approved by the Commission on New Minerals and Mineral Names, International Mineralogical Association in 2008.

Physical properties
Yegorovite is colorless, with a white streak. Found in small quantities among pegmatites. It is a natural silicate of alkali cations.

Chemical composition
The chemical composition of yegorovite in elemental weight percent is as follows:

Crystal structure
The crystal structure of yegorovite is made up of a single chain of four silicon (Si) tetrahedrons [Si4O8(OH)4]∞ and sixfold polyhedrons of [NaO(OH)2(H2O)3] and [NaO(OH)(H2O)4] centered by sodium (Na).