data_global _chemical_name_mineral 'Glaucophane' loop_ _publ_author_name 'Papike J J' 'Clark J R' _journal_name_full 'American Mineralogist' _journal_volume 53 _journal_year 1968 _journal_page_first 1156 _journal_page_last 1173 _publ_section_title ; The crystal structure and cation distribution of glaucophane ; _database_code_amcsd 0000182 _chemical_formula_sum 'Mg2.39 Fe.79 Al1.82 (Na1.96 Ca.04) Si8 O24 H2' _cell_length_a 9.541 _cell_length_b 17.740 _cell_length_c 5.295 _cell_angle_alpha 90 _cell_angle_beta 103.67 _cell_angle_gamma 90 _cell_volume 870.831 _exptl_crystal_density_diffrn 3.084 _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 Mg1 0.00000 0.09080 0.50000 0.84000 0.00481 Fe1 0.00000 0.09080 0.50000 0.16000 0.00481 Al2 0.00000 0.18070 0.00000 0.91000 0.00329 Fe2 0.00000 0.18070 0.00000 0.09000 0.00329 Mg3 0.00000 0.00000 0.00000 0.71000 0.00304 Fe3 0.00000 0.00000 0.00000 0.29000 0.00304 Na4 0.00000 0.27720 0.50000 0.98000 0.01013 Ca4 0.00000 0.27720 0.50000 0.02000 0.01013 Si1 0.28310 0.08710 0.29310 1.00000 0.00393 Si2 0.29200 0.17300 0.80870 1.00000 0.00367 O1 0.10920 0.09270 0.20370 1.00000 0.00633 O2 0.11770 0.17140 0.74800 1.00000 0.00633 O-H3 0.11260 0.00000 0.70880 1.00000 0.00823 O4 0.36790 0.25290 0.80580 1.00000 0.00773 O5 0.35480 0.13180 0.08930 1.00000 0.00811 O6 0.34070 0.12240 0.58140 1.00000 0.00861 O7 0.33170 0.00000 0.30180 1.00000 0.00836