Images
Formula: K(Na,K,☐)9Ca2Ba6Mn2+6Ti6B12Si36O114(O,OH,F)11
Cyclosilicate (ring silicate), borosilicate,
barium-, manganese-,
titanium- and boron- bearing mineral
Crystal System: Hexagonal
Specific gravity: 3.29 measured
Hardness: 6 to 6½
Colour: Olive-green
Tienshanite fuses at 840°C
Common impurities: Fe,Ta,Nb,Mg,Ca,K
Environments
Although tienshanite was approved in 1967, to date (November 2022) it has been reported only from the type
locality.
Localities
At the type locality, the Dara-i-Pioz Glacier, Districts of Republican Subordination, Tajikistan, tienshanite
occurs in a narrow vein of
quartz-aegirine-microcline
pegmatite cutting alkali
syenite. It consists of finely crystalline aggregates up to 5 X 6 cm in
size. Associated minerals include pyrochlore,
astrophyllite, bafertisite,
stillwellite, danburite,
datolite, galena,
titanite and calcite;
datolite sometimes replaces tienshanite
(AM 53.1426).
Back to Minerals