Georgbarsanovite Explained

Georgbarsanovite
Category:Silicate mineral, Cyclosilicate
Formula: (original form)
Imasymbol:Gba[1]
Strunz:9.CO.10 (10 ed)
8/E.23-15 (8 ed)
Dana:64.1.2.2
System:Trigonal
Class:Ditrigonal pyramidal (3m)
(same H-M symbol)
Symmetry:R3m
Unit Cell:a = 14.26, c = 29.95 [Å] (approximated); Z = 3
Color:Yellow-green
Habit:pseudo-octahedra
Cleavage:No
Fracture:Uneven
Tenacity:Brittle
Luster:Vitreous
Streak:White
Diaphaneity:Transparent
Opticalprop:Uniaxial (-)
Refractive:nω 1.64, nε=1.63 (approximated)
Pleochroism:green to pale yellow
Impurities:F, K, Y

Georgbarsanovite is a very rare mineral of the eudialyte group,[2] formerly known under unaccepted name as barsanovite, with formula .[3] The original formula was extended to show the presence of cyclic silicate groups and the domination of silicon at the M4 site.[4] "REE", standing for rare earth elements, is dominated by cerium. Georgbarsanovite is characterized 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 near Petrelius River, Khibiny massif, Kola Peninsula, Russia. It is named after Russian mineralogist Georg Barsanov.

Notes on chemistry

Georgbarsanovite contains admixtures of fluorine, potassium and yttrium, with traces of titanium, hafnium, and barium.

Notes and References

  1. Warr. L.N.. 2021. IMA–CNMNC approved mineral symbols. Mineralogical Magazine. 85. 3. 291–320. 10.1180/mgm.2021.43. 2021MinM...85..291W. 235729616. free.
  2. Mindat, http://www.mindat.org/min-27506.html
  3. Khomyakov, A.P., Nechelyustov, G.N., Ekimenkova, I.A., and Rastsvetayeva, R.K., 2005. Georgbarsanovite,, a mineral species of the eudialyte group: revalidation of barsanovite and the new name of the mineral. Zapiski Rossiyskogo MineralogicheskogoObshchestva 134(6), 47-57 (in Russian, with English abstract)
  4. Johnsen, O., Ferraris, G., Gault, R.A., Grice, D.G., Kampf, A.R., and Pekov, I.V., 2003. The nomenclature of eudialyte-group minerals. The Canadian Mineralogist 41, 785-794