:Locality: Petrelius River, Khibiny, Kola, Russian Federation Size: 0.14 × 0.08 × 0.05 cm Description: A small translucent crystalline fragment from the type locality (TL) of this extremely rare species. This fragment is part of the holotype. Georgbarsanovite is a very rare mineral of the eudialyte group, formerly known under unaccepted name as barsanovite. Barsanovite, described in 1963 as а monoclinic dimorph of trigonal eudialyte, was discredited in 1969 bесаuse its assignment to the monoclinic system had been proved to bе erroneous. Revision study of the barsanovite type specimen carried out with use of the X-ray single crystal analysis has shown that the mineral is trigonal and has а distinct combination of cations and anions in the key sites of the crystal structure. The mineral was revalidated in 2003 as georgbarsanovite given as before after prof. Georgiy Pavlovich Barsanov (1907-1991). [rruff] IMA2003-013 - Discredited monoclinic Barsanovite to trigonal. IMA2007-008 - Determined trigonal structure of georgbarsanovite. Type Locality: Nepheline pegmatite outcrop, Petrelius River, Khibiny Massif, Kola Peninsula, Murmanskaja Oblast', Northern Region, Russia. — Photo: Joan Rosell , from rosellminerals.com · CC BY-SA 4.0
Georgbarsanovite
A very rare eudialyte-group mineral once called barsanovite, with a complex zirconium-bearing formula.
Intro adapted from Wikipedia (CC BY-SA).
Georgbarsanovite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₁₂(Mn,Sr,REE)₃Ca₆Fe²⁺₃Zr₃NbSi₂₅O₇₆Cl₂·H₂O.
It crystallizes in the hexagonal crystal system (space group R3m). It is a member of the Eudialyte structural group.
Key properties: Mohs hardness 5; specific gravity 3.05; White streak; Vitreous luster; optically uniaxial.
IMA symbol Gba, IMA status: approved, named in 2003.
A late stage reaction product in nepheline-feldspar pegmatite in association with an alkaline massif.
It is found associated with Eudialyte.
The mineral was named to honor prominent Russian mineralogist Georgiy Pavlovich Barsanov (1907-1991).