data_global
_chemical_name_mineral 'Schorl'
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: Schorl 2672
;
_database_code_amcsd 0018784
_chemical_compound_source 'Silver Crater, Hastings Co., Ontario, Canada'
_chemical_formula_sum '(Na.99 Ca.01) Fe3.828 Mg1.269 V.021 Al3.42 Ti.402 Si6 B3 O31 H3.6'
_cell_length_a 16.073
_cell_length_b 16.073
_cell_length_c 7.306
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 1634.573
_exptl_crystal_density_diffrn      3.294
_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   0.23010   0.99000   0.02670
CaX   0.00000   0.00000   0.23010   0.01000   0.02670
Fe2Y   0.12356   0.06178   0.63534   0.75600   0.00900
MgY   0.12356   0.06178   0.63534   0.23700   0.00900
VY   0.12356   0.06178   0.63534   0.00700   0.00900
AlZ   0.29853   0.26198   0.61195   0.57000   0.00610
Fe3Z   0.29853   0.26198   0.61195   0.26000   0.00610
MgZ   0.29853   0.26198   0.61195   0.09300   0.00610
TiZ   0.29853   0.26198   0.61195   0.06700   0.00610
SiT   0.19081   0.18917   0.00000   1.00000   0.00640
B   0.11010   0.22020   0.45540   1.00000   0.00920
O1   0.00000   0.00000   0.78000   1.00000   0.02020
O2   0.06145   0.12290   0.48440   1.00000   0.01080
O3   0.26580   0.13290   0.51220   1.00000   0.01380
O4   0.09252   0.18504   0.06860   1.00000   0.01130
O5   0.18348   0.09174   0.08750   1.00000   0.01100
O6   0.19557   0.18640   0.78060   1.00000   0.01010
O7   0.28323   0.28328   0.07830   1.00000   0.01090
O8   0.20850   0.26960   0.44220   1.00000   0.01240
H1   0.00000   0.00000   0.65500   0.60000   0.01000
H3   0.25400   0.12700   0.41600   1.00000   0.01000