Vivianite
Diffraction data computed using the structure from the paper listed below,
along with the cell parameters refined from the powder pattern for R040185
      Takagi S, Mathew M, Brown W E
      American Mineralogist 71 (1986) 1229-1233
      Crystal structures of bobierrite and synthetic Mg3(PO4)2.8H2O

      CELL PARAMETERS:   10.03400   13.40700   4.657000   90.00000   105.0900   90.00000
      SPACE GROUP: C2/m
      X-RAY WAVELENGTH:     1.541838
               2-THETA      INTENSITY    D-SPACING   H   K   L
                11.19         32.88        7.9114    1   1   0
                13.22        100.00        6.6978    0   2   0
                18.09          4.75        4.9019    2   0   0
                20.58         13.14        4.3145   -1   1   1
                21.87          1.63        4.0636    1   3   0
                22.47          4.05        3.9557    2   2   0
                23.13          8.60        3.8443   -2   0   1
                23.82          1.43        3.7338    0   2   1
                24.71          3.27        3.6012    1   1   1
                26.61          1.74        3.3489    0   4   0
                27.96         19.07        3.1895   -1   3   1
                28.09          6.93        3.1749    3   1   0
                30.10         17.83        2.9675   -3   1   1
                30.22         13.85        2.9560    2   0   1
                32.36          3.26        2.7652    2   4   0
                33.11         18.72        2.7043    2   2   1
                33.34         17.15        2.6860    0   4   1
                33.98          4.48        2.6371    3   3   0
                35.53         24.22        2.5252   -2   4   1
                35.69          1.83        2.5146   -3   3   1
                36.65          5.50        2.4510    4   0   0
                36.95          9.30        2.4316   -4   0   1
                38.57          1.09        2.3330    3   1   1
                38.98          2.80        2.3096   -1   5   1
                39.29          2.41        2.2921   -1   1   2
                39.40          2.09        2.2857   -4   2   1
                40.08          3.30        2.2487    0   0   2
                40.69         11.63        2.2162    2   4   1
                41.44          4.15        2.1777    1   5   1
                41.85          1.52        2.1573   -2   2   2
                43.05          1.24        2.0999   -3   1   2
                43.66          2.94        2.0719    3   5   0
                44.07          3.18        2.0536    1   1   2
                45.32          2.67        1.9998    0   6   1
                46.10          2.85        1.9677   -4   4   1
                45.95          2.60        1.9740   -5   1   1
                47.04          3.29        1.9306   -2   6   1
                46.80          1.63        1.9401    5   1   0
                47.33          3.10        1.9196   -3   3   2
                47.26          3.65        1.9222   -4   0   2
                48.28          4.67        1.8841    1   3   2
                48.44          1.14        1.8782    1   7   0
                48.68          2.20        1.8694    2   0   2
                50.03          1.49        1.8220   -5   3   1
                51.46          1.88        1.7748    3   5   1
                51.78          1.06        1.7644   -1   7   1
                52.03          1.17        1.7566   -1   5   2
                54.79          5.42        1.6745    0   8   0
                55.11          5.63        1.6654   -3   5   2
                55.96          5.53        1.6421    1   5   2
                56.33          1.09        1.6323    2   4   2
                56.19          1.02        1.6361    5   1   1
                57.55          3.12        1.6005   -5   5   1
                58.28          3.41        1.5823    5   5   0
                58.07          2.87        1.5874    6   2   0
                59.76          1.86        1.5464    5   3   1
                60.84          2.96        1.5215   -6   0   2
                61.70          3.56        1.5025   -6   4   1
                62.84          1.52        1.4779   -1   7   2
                62.83          4.33        1.4780    4   0   2
                63.80          1.77        1.4580   -1   3   3
                63.85          1.82        1.4569    2   8   1
                65.72          1.14        1.4199    1   1   3
                66.43          2.45        1.4064   -2   4   3
                68.53          1.32        1.3683    0   4   3
                70.22          2.97        1.3396    0  10   0
                70.38          2.65        1.3368   -1   5   3
                70.37          2.29        1.3370   -3   9   1
                70.01          1.14        1.3430   -6   6   1
                71.32          1.33        1.3215   -3   5   3
                76.56          1.87        1.2435    7   1   1
                76.73          1.86        1.2412    7   5   0
                78.31          1.39        1.2201    2  10   1
                82.95          1.43        1.1632   -2   0   4
                86.33          1.24        1.1261   -6   8   2
                88.09          1.19        1.1081    4   8   2
                88.09          1.19        1.1081    4   8   2
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.