Tumchaite Mineral Data

General Tumchaite Information
Chemical Formula:	Na2(Zr,Sn)Si4O11•2(H2O)
Composition:	Molecular Weight = 462.51 gm
	Sodium 9.94 % Na 13.40 % Na₂O
	Zirconium 14.79 % Zr 19.98 % ZrO₂
	Silicon 24.29 % Si 51.96 % SiO₂
	Tin 5.13 % Sn 6.52 % SnO₂
	Hydrogen 0.87 % H 7.79 % H₂O
	Oxygen 44.97 % O
	______ ______
	100.00 % 99.65 % = TOTAL OXIDE
Empirical Formula:	Na₂Zr_0.75Sn_0.2Si₄O₁₁•2(H₂O)
Environment:	From a core sample of rocks formed by the hydrothermal alteration of dolomite-calcite carbonatites. Zr-analogue of penkvilksite-1M
IMA Status:	Approved IMA 1999 (Dana # Added)
Locality:	Vuoriyarvi alkali-ultrabasic massif, North Karelia on the north shore of the Vuoriyarvi lake, Murmansk Region, Russia. Link to MinDat.org Location Data.
Name Origin:	The mineral is named for the river Tumcha near Vuoriyarvi massif.
Synonym:	ICSD 89740
	IMA1999-041