data_global
_chemical_name_mineral 'Osumilite'
loop_
_publ_author_name
'Armbruster T'
'Oberhansli R'
_journal_name_full 'American Mineralogist'
_journal_volume 73 
_journal_year 1988
_journal_page_first 585
_journal_page_last 594
_publ_section_title
;
 Crystal chemistry of double-ring silicates: Structural, chemical, and optical
 variation in osumilites
 Sample: Antarctica
;
_database_code_amcsd 0001149
_chemical_formula_sum 'K.91 (Fe.05 Mg1.98) Si10.32 Al4.65 O30'
_cell_length_a 10.086
_cell_length_b 10.086
_cell_length_c 14.325
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 1262.011
_exptl_crystal_density_diffrn      2.584
_symmetry_space_group_name_H-M 'P 6/m c c'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-x+y,1/2+z'
  'x,x-y,1/2-z'
  '-x+y,-x,-z'
  'x-y,x,z'
  '-y,-x,1/2+z'
  'y,x,1/2-z'
  'y,-x+y,-z'
  '-y,x-y,z'
  'x-y,-y,1/2+z'
  '-x+y,y,1/2-z'
  'x,y,-z'
  '-x,-y,z'
  'x,x-y,1/2+z'
  '-x,-x+y,1/2-z'
  'x-y,x,-z'
  '-x+y,-x,z'
  'y,x,1/2+z'
  '-y,-x,1/2-z'
  '-y,x-y,-z'
  'y,-x+y,z'
  '-x+y,y,1/2+z'
  'x-y,-y,1/2-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
KC   0.00000   0.00000   0.25000   0.91000
FeA   0.33333   0.66667   0.25000   0.01000
MgA   0.33333   0.66667   0.25000   0.99000
Si1   0.24821   0.35359   0.39206   0.86000
Al1   0.24821   0.35359   0.39206   0.14000
Fe2   0.50000   0.50000   0.25000   0.01000
Al2   0.50000   0.50000   0.25000   0.99000
O1   0.12290   0.40790   0.00000   1.00000
O2   0.21660   0.28470   0.13200   1.00000
O3   0.13980   0.49340   0.17900   1.00000
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
KC 0.02550 0.02550 0.03100 0.01275 0.00000 0.00000
FeA 0.00540 0.00540 0.01070 0.00270 0.00000 0.00000
MgA 0.00540 0.00540 0.01070 0.00270 0.00000 0.00000
Si1 0.00860 0.00990 0.00770 0.00550 0.00150 0.00170
Al1 0.00860 0.00990 0.00770 0.00550 0.00150 0.00170
Fe2 0.00910 0.00910 0.00680 0.00720 0.00000 0.00000
Al2 0.00910 0.00910 0.00680 0.00720 0.00000 0.00000
O1 0.02600 0.02000 0.00720 0.01100 0.00000 0.00000
O2 0.02800 0.03500 0.02280 0.02440 -0.00170 -0.00480
O3 0.01380 0.01550 0.01170 0.00870 -0.00370 -0.00490