Fluor-dravite
Clark C M, Hawthorne F C, Ottolini L
The Canadian Mineralogist 49 (2011) 57-62
Fluor-dravite, NaMg3Al6Si6O18(BO3)3(OH)3F, a new mineral species of the tourmaline
group from the Crabtree Emerald mine, Mitchell County, North Carolina:
Description and crystal structure
Locality: the Crabtree Emerald mine, Mitchell County, North Carolina, USA
_database_code_amcsd 0018741
15.955 15.955 7.153 90 90 120 R3m
atom       x      y       z occ  Uiso
NaX        0      0  .84080 .88 .0209
CaX        0      0  .84080 .04 .0209
MgY   .06312 .93688  .44473 .43 .0088
FeY   .06312 .93688  .44473 .29 .0088
AlY   .06312 .93688  .44473 .19 .0088
MnY   .06312 .93688  .44473 .03 .0088
TiY   .06312 .93688  .44473 .01 .0088
LiY   .06312 .93688  .44473 .04 .0088
AlZ   .26174 .29827  .45757 .91 .0071
MgZ   .26174 .29827  .45757 .09 .0071
SiT   .19009 .19191  .07041     .0067
B     .88998 .11002  .61615     .0082
F1         0      0  .29119 .61 .0197
OH1        0      0  .29119 .39 .0197
OH2   .93841 .06159  .59029     .0122
O3    .13491 .86509  .55913     .0114
O4    .90702 .09298  .00075     .0109
O5    .09271 .90729 -.02049     .0108
O6    .18803 .19746  .29369     .0094
O7    .28527 .28493 -.01074     .0092
O8    .27133 .21031  .62784     .0100