AM_Oxy-dravite_2 Formula: Na.477 Ca.412 K.015 Mg2.784 Al5.262 V.831 Cr.168 Ti.027 Zn.015 Fe.006 Mn.003 Si5.91 B3 O30.685 F.314 H.248 Name: Oxy-dravite Unit cell: 15.9706 15.9706 7.2276 90.0 90.0 120.0 , V=1596.49 Space group: R3M (160)

Bosi F , Lucchesi S , European Journal of Mineralogy , 16 (2004) p.335-344, Crystal chemistry of the schorl-dravite series, Note: Tourmaline TM504c, Locality: Olkhon (Lake Baikal), Siberia