Tienshanite

 Tienshanite, named for the Tian Shan Range in Mongolia, is a rare borosilicate mineral, though rock-forming in some parts of its original locality at the Dara-i-Pioz Glacier in Tajikistan.[1][2][3] Its formula is extremely complex: KNa3(Na,K,[])6(Ca,Y,RE)2Ba6(Mn2+,Fe2+,Zn,Ti)6(Ti,Nb)6Si36B12O114[O5.5(OH,F)3.5]F2.[4]

Tienshanite
Tienshanite.jpg
General
CategoryCyclosilicate
Formula
(repeating unit)		KNa3(Na,K,[])6(Ca,Y,RE)2Ba6(Mn2+,Fe2+,Zn,Ti)6
(Ti,Nb)6Si36B12O114[O5.5(OH,F)3.5]F2
Strunz classification9.CL.05
Crystal systemHexagonal
Crystal classDipyramidal (6/m)
H-M symbol: (6/m)
Space groupHexagonal
Space group: P6/m
Identification
Colorolive-green
Mohs scale hardness6 - ​6 1⁄2
Lustervitreous
References[1][2]

This article uses material from the Wikipedia article
 Metasyntactic variable, which is released under the 
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