data_global
_chemical_name_mineral 'Fluor-buergerite'
loop_
_publ_author_name
'Grice J D'
'Ercit T S'
_journal_name_full 'Neues Jahrbuch fur Mineralogie, Abhandlungen'
_journal_volume 165 
_journal_year 1993
_journal_page_first 245
_journal_page_last 266
_publ_section_title
;
 Ordering of Fe and Mg in the tourmaline crystal structure: The correct formula
 Sample: Buergerite 43293
;
_database_code_amcsd 0018787
_chemical_compound_source 'Mapimi, Durango, Mexico'
_chemical_formula_sum 'Na.88 Ca.04 Fe2.53 Al6.41 Mg.06 Si5.83 B3.1 Ti.07 F.74 O30.26 H1.35'
_cell_length_a 15.874
_cell_length_b 15.874
_cell_length_c 7.196
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 1570.343
_exptl_crystal_density_diffrn      3.292
_symmetry_space_group_name_H-M 'R 3 m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '2/3+x,1/3+y,1/3+z'
  '1/3+x,2/3+y,2/3+z'
  'x,x-y,z'
  '2/3+x,1/3+x-y,1/3+z'
  '1/3+x,2/3+x-y,2/3+z'
  '-y,-x,z'
  '2/3-y,1/3-x,1/3+z'
  '1/3-y,2/3-x,2/3+z'
  '-x+y,y,z'
  '2/3-x+y,1/3+y,1/3+z'
  '1/3-x+y,2/3+y,2/3+z'
  '-y,x-y,z'
  '2/3-y,1/3+x-y,1/3+z'
  '1/3-y,2/3+x-y,2/3+z'
  '-x+y,-x,z'
  '2/3-x+y,1/3-x,1/3+z'
  '1/3-x+y,2/3-x,2/3+z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
NaX   0.00000   0.00000   0.21540   0.88000   0.02420
CaX   0.00000   0.00000   0.21540   0.04000   0.02420
Fe3Y   0.13246   0.06623   0.62230   0.55000   0.01190
AlY   0.13246   0.06623   0.62230   0.30330   0.01190
Fe2Y   0.13246   0.06623   0.62230   0.12670   0.01190
MgY   0.13246   0.06623   0.62230   0.02000   0.01190
AlZ   0.29865   0.25865   0.60440   0.91670   0.00670
FeZ   0.29865   0.25865   0.60440   0.08330   0.00670
SiT   0.19151   0.19048   0.00000   0.97170   0.00540
BT   0.19151   0.19048   0.00000   0.01670   0.00540
TiT   0.19151   0.19048   0.00000   0.01170   0.00540
B   0.11010   0.22020   0.45230   1.00000   0.00750
F1   0.00000   0.00000   0.76810   0.74000   0.01810
O1   0.00000   0.00000   0.76810   0.26000   0.01810
O2   0.06047   0.12094   0.48630   1.00000   0.00900
O3   0.26358   0.13179   0.52050   0.55000   0.00900
O-H3   0.26358   0.13179   0.52050   0.45000   0.00900
O4   0.09452   0.18904   0.07540   1.00000   0.00940
O5   0.18232   0.09116   0.08460   1.00000   0.01010
O6   0.19280   0.18650   0.77510   1.00000   0.00810
O7   0.28680   0.28600   0.07500   1.00000   0.00770
O8   0.20950   0.27000   0.43850   1.00000   0.00770