AM_Britvinite Formula: Si10.532 Mg9 Pb14.144 C2 B3.468 O58 F2 Name: Britvinite Unit cell: 9.3409 9.3579 18.8333 80.365 75.816 59.87 , V=1378.47 Space group: P-1 (2)

Yakubovich O V , Massa W , Chukanov N V , Crystallography Reports , 53 (2008) p.206-215, Crystal structure of britvinite [Pb7(OH)3F(BO3)2(CO3)][Mg4.5(OH)3(Si5O14)]:, A new layered silicate with an original type of silicon-oxygen networks, Locality: Varmland, Sweden