Tugtupite_17 Formula: Al Be Si4 O12 Na4 Cl Name: Tugtupite Unit cell: 8.64 8.64 8.873 90.0 90.0 90.0 , V=662.37 Space group: I1-41 (1)
Hassan I , Grundy H D , The Canadian Mineralogist , 29 (1991) p.385-390, The crystal structure and thermal expansion of tugtupite,, Na8[Al2Be2Si8O24]Cl2