data_global
_chemical_name_mineral 'Pargasite'
loop_
_publ_author_name
'Comodi P'
'Mellini M'
'Ungaretti L'
'Zanazzi P F'
_journal_name_full 'European Journal of Mineralogy'
_journal_volume 3 
_journal_year 1991
_journal_page_first 485
_journal_page_last 499
_publ_section_title
;
 Compressibility and high pressure structure refinement
 of tremolite, pargasite and glaucophane
 Sample: pressure at ambient conditions (.001 kbar)
;
_database_code_amcsd 0006418
_chemical_formula_sum 'Na.74 K.02 Mg4.26 Fe.21 Al1.68 Cr.18 Ti.07 Ca1.98 Si6.62 O24 H2'
_cell_length_a 9.881
_cell_length_b 17.998
_cell_length_c 5.284
_cell_angle_alpha 90
_cell_angle_beta 105.25
_cell_angle_gamma 90
_cell_volume 906.608
_exptl_crystal_density_diffrn      3.086
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-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
NaA   0.00000   0.50000   0.00000   0.26000   0.04000
NaAM   0.04600   0.50000   0.12970   0.12000   0.04300
NaA2   0.00000   0.46660   0.00000   0.12000   0.02500
KA2   0.00000   0.46660   0.00000   0.01000   0.02500
MgM1   0.00000   0.08880   0.50000   0.94500   0.00580
FeM1   0.00000   0.08880   0.50000   0.05500   0.00580
MgM2   0.00000   0.17610   0.00000   0.72500   0.00450
AlM2   0.00000   0.17610   0.00000   0.15000   0.00450
CrM2   0.00000   0.17610   0.00000   0.09000   0.00450
TiM2   0.00000   0.17610   0.00000   0.03500   0.00450
MgM3   0.00000   0.00000   0.00000   0.92000   0.00460
FeM3   0.00000   0.00000   0.00000   0.08000   0.00460
CaM4   0.00000   0.27910   0.50000   0.49000   0.00960
FeM4   0.00000   0.27910   0.50000   0.01000   0.00960
CaM42   0.46530   0.21980   0.61680   0.25000   0.04500
SiT1   0.27970   0.08500   0.30220   0.65500   0.00520
AlT1   0.27970   0.08500   0.30220   0.34500   0.00520
SiT2   0.28990   0.17260   0.81120   1.00000   0.00560
O1   0.10770   0.08730   0.21850   1.00000   0.00880
O2   0.11930   0.17290   0.73060   1.00000   0.00890
O3   0.10770   0.00000   0.71520   1.00000   0.01030
O4   0.36640   0.24940   0.78870   1.00000   0.01020
O5   0.34840   0.13900   0.10960   1.00000   0.01120
O6   0.34360   0.11640   0.60640   1.00000   0.01250
O7   0.33820   0.00000   0.27950   1.00000   0.01320
H   0.17500   0.00000   0.74800   1.00000   0.01200