Georgbarsanovite
Georgbarsanovite is a very rare mineral of the eudialyte group, formerly known under unaccepted name as barsanovite, with formula Na123Ca6Fe32+Zr3NbSi22O4Cl2•H2O. The original formula was extended to show the presence of cyclic silicate groups and domination of silicon at the M4 site. "REE", standing for rare earth elements, are dominated by cerium. Georgbarsanovite characterizes in dominance of manganese at the N4 site. It also differs from most other accepted group representatives in its colour. The mineral was found in nepheline pegmatite nearby Petrelius river, Khibiny massif, Kola Peninsula, Russia. It is named after Russian mineralogist Georg Barsanov.
