Dravite Bosi F, Lucchesi S European Journal of Mineralogy 16 (2004) 335-344 Crystal chemistry of the schorl-dravite series Note: Tourmaline TM235b Locality: Beresov Mine, Siberia _database_code_amcsd 0007041 15.9388 15.9388 7.2050 90 90 120 R3m atom x y z occ NaX 0 0 .23498 .724 CaX 0 0 .23498 .094 KX 0 0 .23498 .003 AlY .12457 .062285 .63361 .429 MgY .12457 .062285 .63361 .384 Fe2+Y .12457 .062285 .63361 .162 Ti4+Y .12457 .062285 .63361 .021 ZnY .12457 .062285 .63361 .004 V3+Y .12457 .062285 .63361 .001 Cr3+Y .12457 .062285 .63361 .001 AlZ .29805 .26158 .61157 .833 MgZ .29805 .26158 .61157 .152 Fe3+Z .29805 .26158 .61157 .012 Fe2+Z .29805 .26158 .61157 .003 SiT .19177 .18985 0 .997 AlT .19177 .18985 0 .003 B .10976 .21952 .45507 OH1W 0 0 .77293 .572 O1W 0 0 .77293 .382 F1W 0 0 .77293 .046 O2 .06081 .12162 .48753 OH3V .26373 .131865 .51141 O4 .09306 .18612 .07048 O5 .18431 .092155 .09189 O6 .19546 .18516 .77772 O7 .28506 .28497 .07892 O8 .20920 .26991 .44101