AM_Chromdravite Formula: Na.88 Ca.073 K.017 Cr4.347 Mg2.244 V.354 Fe.051 Zn.021 Ti.003 Al2.1 Si5.886 B3 O30.618 F.381 H3.009 Name: Chromdravite Unit cell: 16.0539 16.0539 7.3247 90.0 90.0 120.0 , V=1634.86 Space group: R3M (160)

Bosi F , Lucchesi S , Reznitskii L , European Journal of Mineralogy , 16 (2004) p.345-352, Crystal chemistry of the dravite-chromdravite series, Note: Tourmaline TMt3b, Locality: Sludyanka crystalline complex, Lake Baikal, Russia