data_global _chemical_name_mineral 'Ankerite' loop_ _publ_author_name 'Reeder R J' 'Dollase W A' _journal_name_full 'American Mineralogist' _journal_volume 74 _journal_year 1989 _journal_page_first 1159 _journal_page_last 1167 _publ_section_title ; Structural variation in the dolomite-ankerite solid-solution series: An X-ray, Mossbauer, and TEM study sample AMNH 8059 ; _database_code_amcsd 0001274 _chemical_formula_sum 'Ca.997 Fe.73 Mg.273 C2 O6' _cell_length_a 4.8312 _cell_length_b 4.8312 _cell_length_c 16.1663 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 326.777 _exptl_crystal_density_diffrn 3.161 _symmetry_space_group_name_H-M 'R -3' 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' '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' '-x,-y,-z' '2/3-x,1/3-y,1/3-z' '1/3-x,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 CaA 0.00000 0.00000 0.00000 0.97800 FeA 0.00000 0.00000 0.00000 0.02200 MgB 0.00000 0.00000 0.50000 0.27300 FeB 0.00000 0.00000 0.50000 0.70800 CaB 0.00000 0.00000 0.50000 0.01900 C 0.00000 0.00000 0.24395 1.00000 O 0.25045 -0.02842 0.24496 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 CaA 0.00971 0.00971 0.00878 0.00486 0.00000 0.00000 FeA 0.00971 0.00971 0.00878 0.00486 0.00000 0.00000 MgB 0.00713 0.00713 0.00838 0.00357 0.00000 0.00000 FeB 0.00713 0.00713 0.00838 0.00357 0.00000 0.00000 CaB 0.00713 0.00713 0.00838 0.00357 0.00000 0.00000 C 0.00869 0.00869 0.00927 0.00435 0.00000 0.00000 O 0.01011 0.01428 0.01615 0.00789 -0.00260 -0.00363