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.Mindat.org – TienshaniteWebmineral.com – TienshaniteHandbook of Mineralogy – Tienshanite Its formula is extremely complex: .Cooper M. A., Hawthorne F. C. and Grew E. S. 1998: Refinement of the crystal structure of tienshanite: short-range-order constrains on chemical composition. The Canadian Mineralogist, 36, pp. 1305–1310

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