AM_Vuonnemite Formula: Si4 P2 Nb2 Ti2 Na11 O26 Name: Vuonnemite Unit cell: 5.4984 7.161 14.45 92.6 95.3 90.6 , V=565.88 Space group: P-1 (2)

Ercit T S , Cooper M A , Hawthorne F C , The Canadian Mineralogist , 36 (1998) p.1311-1320, The crystal structure of vuonnemite, Na11TiNb2(Si2O7)2(PO4)2O3(F,OH),, a phosphate-bearing sorosilicate of the lomonosovite group, Locality: Ilimaussaq, Greenland