Iowaite
      Zhitova E S, Chukanov N V, Pekov I V, Zolotarev A A, Shilovskikh V V, Bocharov V N
      Applied Clay Science 243 (2023) 107070
      Crystal chemistry of iowaite, Mg6FeIII2(OH)16Cl2 x 4H2O, a natural layered double hydroxide
      Locality: Talnakh, Russia
      _database_code_amcsd 0021230

      CELL PARAMETERS:    3.1077   3.1077  23.8850   90.000   90.000  120.000
      SPACE GROUP: R-3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    199.772
      Density (g/cm3):      2.061
      MAX. ABS. INTENSITY / VOLUME**2:      26.38313948    
      RIR:      4.168
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                11.11        100.00        7.9617    0   0   3         2
                22.33         26.34        3.9808    0   0   6         2
                34.15         17.90        2.6255    0   1   2         6
                38.39         22.15        2.3448    0   1   5         6
                45.37         20.40        1.9990    0   1   8         6
                51.13          4.58        1.7864    1   0  10         6
                54.28          5.16        1.6899    0   1  11         6
                59.49          6.81        1.5539    1   1   0         6
                60.73          7.80        1.5251    1   1   3        12
                61.07          3.62        1.5174    1   0  13         6
                64.36          2.61        1.4475    1   1   6        12
                64.69          1.46        1.4409    0   1  14         6
                72.39          2.80        1.3054    1   0  16         6
                73.05          2.10        1.2953    2   0   5         6
                77.86          1.85        1.2268    2   0   8         6
                84.75          1.03        1.1438    2   0  11         6
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       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.