data_global
_chemical_name_mineral 'Tumchaite'
loop_
_publ_author_name
'Subbotin V V'
'Merlino S'
'Pushcharovsky D Y'
'Pakhomovsky Y A'
'Ferro O'
'Bogdanova A N'
'Voloshin A V'
'Sorokhtina N V'
'Zubkova N V'
_journal_name_full 'American Mineralogist'
_journal_volume 85 
_journal_year 2000
_journal_page_first 1516
_journal_page_last 1520
_publ_section_title
;
 Tumchaite Na2(Zr,Sn)Si4O11.2H2O - a new mineral from carbonatites of the
 Vuoriyarvi alkali-ultrabasic massif, Murmansk Region, Russia
;
_database_code_amcsd 0002590
_chemical_formula_sum '(Zr.8 Sn.2) Si4 Na2 O13 H4'
_cell_length_a 9.144
_cell_length_b 8.818
_cell_length_c 7.537
_cell_angle_alpha 90
_cell_angle_beta 113.22
_cell_angle_gamma 90
_cell_volume 558.495
_exptl_crystal_density_diffrn      2.777
_symmetry_space_group_name_H-M 'P 1 21/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2-y,1/2+z'
  '-x,1/2+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
_atom_site_U_iso_or_equiv
Zr   0.00000   0.50000   0.00000   0.80000   0.00760
Sn   0.00000   0.50000   0.00000   0.20000   0.00760
Si1   0.16690   0.15820   0.19930   1.00000   0.00930
Si2   0.31760   0.44210   0.41240   1.00000   0.00930
Na   0.20510   0.68840   0.71090   1.00000   0.02430
O1   0.31480   0.26590   0.34540   1.00000   0.01290
O2   0.11640   0.03460   0.31870   1.00000   0.01260
O3   0.02600   0.26760   0.06600   1.00000   0.01310
O4   0.24710   0.05430   0.07910   1.00000   0.01310
O5   0.21450   0.54250   0.22990   1.00000   0.01200
O6   0.50000   0.00000   0.00000   1.00000   0.01570
OW   0.37090   0.69210   0.03710   1.00000   0.03170
H1   0.49800   0.68400   0.07500   1.00000   0.05000
H2   0.35200   0.60200   0.09000   1.00000   0.05000