Tuesday 01 - Mineralogy of natural zeolites

Karpinsky All-Russia Geological Research Institute (VSEGEI), mvn(. mail. wplus. net 

Al ordering in a dachiardite framework was examined based on the structural data and Si MAS NMR spectra. Obtained ordered distribution model of dachiardite contains four Al atoms per unit cell, and its space group was P2/m instead of the conventional C2/m. Al atoms are located on T3 and T4 sites which construct 4 rings. Because Al content in a mined sample is larger than four, small amount of Si atoms should be substituted by Al atoms and some extent of Al atoms move to another site in order to satisfy the Loewenstein s rule. Simulated NMR spectrum based on this substitution was in excellent agreement with the observed ones. 

Ol-P-08 - Chemical composition and ion-exchange properties of a natrolite from Zahedan region, Iran 

Ol-P-09 - Physical, chemical and structural characterization of the volcanic tuff from the Maramures area, Romania 

Pode (a), G. Burtica (a), S. Herman (a), A. lovi (a) and I. Calb (b) a University Politehnica of Timisoara, Romania, Email tcapm rectorat.utt.ro b Cemacom SA, 4700 Zalau, Romania, Fax +40 60 661003 

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