data_global _chemical_name_mineral 'Dravite' loop_ _publ_author_name 'Vereshchagin O S' 'Rozhdestvenskaya I V' 'Frank-Kamenetskaya O V' 'Zolotarev A A' _journal_name_full 'European Journal of Mineralogy' _journal_volume 26 _journal_year 2014 _journal_page_first 309 _journal_page_last 321 _publ_section_title ; Ion substitutions and structural adjustment in Cr-bearing tourmalines Note: Sample 2 ; _database_code_amcsd 0020155 _chemical_compound_source 'Shabrovskoe ore district, Middle Urals, Russia' _chemical_formula_sum 'Ca.02 Na.76 K.01 Al5.91 Cr.72 Fe.09 Mg2.34 Si5.94 B3 O31 H3.68' _cell_length_a 15.933 _cell_length_b 15.933 _cell_length_c 7.213 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 1585.775 _exptl_crystal_density_diffrn 3.067 _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 CaX 0.00000 0.00000 0.22970 0.02000 0.01810 NaX 0.00000 0.00000 0.22970 0.76000 0.01810 KX 0.00000 0.00000 0.22970 0.01000 0.01810 AlY 0.12367 0.06184 0.63640 0.65000 0.00520 CrY 0.12367 0.06184 0.63640 0.08000 0.00520 FeY 0.12367 0.06184 0.63640 0.01000 0.00520 MgY 0.12367 0.06184 0.63640 0.26000 0.00520 AlZ 0.29776 0.26152 0.61006 0.65000 0.00440 CrZ 0.29776 0.26152 0.61006 0.08000 0.00440 FeZ 0.29776 0.26152 0.61006 0.01000 0.00440 MgZ 0.29776 0.26152 0.61006 0.26000 0.00440 SiT 0.19153 0.18969 0.00000 0.99000 0.00450 AlT 0.19153 0.18969 0.00000 0.01000 0.00450 B 0.10991 0.21982 0.45370 1.00000 0.00600 O-Hw 0.00000 0.00000 0.76930 0.92000 0.01000 O1w 0.00000 0.00000 0.76930 0.08000 0.01000 O2 0.06062 0.12124 0.48720 1.00000 0.01100 O-Hv 0.26074 0.13037 0.50980 0.92000 0.01020 O3v 0.26074 0.13037 0.50980 0.08000 0.01020 O4 0.09316 0.18632 0.07090 1.00000 0.00880 O5 0.18442 0.09221 0.09220 1.00000 0.00790 O6 0.19430 0.18417 0.77690 1.00000 0.00760 O7 0.28483 0.28468 0.07730 1.00000 0.00790 O8 0.20900 0.26970 0.43880 1.00000 0.00930