Beryl
Diffraction data computed using the structure from the paper listed below, 
along with the cell parameters refined from the powder pattern of R050065
      Aurisicchio C, Fioravanti G, Grubessi O, Zanazzi P F
      American Mineralogist 73 (1988) 826-837
      Reappraisal of the crystal chemistry of beryl
      Sample: 6

      CELL PARAMETERS:   9.2165  9.2165  9.2181   90.000   90.000  120.000
      SPACE GROUP: P6/mcc    

           ATOM        X         Y         Z     OCCUPANCY  ISO(B)
            Si     0.38630   0.11390   0.00000     1.000     0.344
            Be     0.50000   0.00000   0.25000     0.959     0.632
            Li     0.50000   0.00000   0.25000     0.033     0.632
            Si     0.50000   0.00000   0.25000     0.008     0.632
            Al     0.66667   0.33333   0.25000     0.826     0.503
            Fe     0.66667   0.33333   0.25000     0.020     0.503
            Fe     0.66667   0.33333   0.25000     0.097     0.503
            Mg     0.66667   0.33333   0.25000     0.058     0.503
            O      0.30640   0.23260   0.00000     1.000     1.014
            O      0.49600   0.14340   0.14510     1.000     0.755
            Na     0.00000   0.00000   0.25000     0.315     2.317
            Cs     0.00000   0.00000   0.25000     0.040     2.317

            X-RAY WAVELENGTH:     1.541838
            BOUNDS ON TWO THETA:    5.0  90.0
            LIMITS IMPOSED ON THE INDICES ARE:  +/-  7 +/-  7 +/-  8
            MAX. ABS. INTENSITY / VOLUME**2:      12.11335352    
            The INTENSITY cut off value is   1.00

               2-THETA      INTENSITY    D-SPACING   H   K   L
                11.09        100.00        7.9817    1   0   0
                19.26         33.24        4.6090    0   0   2
                19.26          4.51        4.6083    1   1   0
                22.27         17.60        3.9914    1   0   2
                22.28          4.38        3.9909    2   0   0
                27.37         92.58        3.2588    1   1   2
                29.61         26.29        3.0170    2   0   2
                29.61          6.75        3.0168    2   1   0
                31.20         90.73        2.8672    2   1   1
                33.69          1.58        2.6606    3   0   0
                35.57         13.07        2.5242    2   1   2
                39.09          7.23        2.3045    0   0   4
                40.75          2.67        2.2141    1   0   4
                40.76          3.10        2.2137    3   1   0
                41.97          1.13        2.1527    2   1   3
                41.97          6.13        2.1525    3   1   1
                43.93          2.09        2.0612    1   1   4
                45.45          7.64        1.9957    2   0   4
                45.45          1.30        1.9955    3   1   2
                45.45          2.68        1.9954    4   0   0
                49.80          2.40        1.8311    3   2   0
                50.83          9.85        1.7961    3   1   3
                52.54         11.63        1.7419    3   0   4
                52.54          8.99        1.7418    4   1   0
                53.54          8.06        1.7115    4   1   1
                53.87          1.65        1.7017    3   2   2
                56.48         12.18        1.6294    2   2   4
                56.48          2.19        1.6293    4   1   2
                57.75          1.31        1.5965    3   1   4
                57.75          4.32        1.5963    5   0   0
                58.69          2.72        1.5731    2   1   5
                58.69          5.20        1.5730    3   2   3
                60.24          4.53        1.5363    0   0   6
                61.16         14.12        1.5152    4   1   3
                61.47          1.56        1.5084    4   2   0
                63.87          5.12        1.4575    1   1   6
                63.88          4.77        1.4573    3   3   2
                65.06          4.33        1.4337    3   2   4
                65.06          4.47        1.4336    4   2   2
                68.54          2.96        1.3690    2   1   6
                68.55          2.80        1.3689    5   1   2
                72.79          1.03        1.2992    3   2   5
                74.19          1.72        1.2783    2   2   6
                74.19          8.47        1.2781    6   0   2
                74.20          3.37        1.2781    5   2   0
                75.02          4.59        1.2661    4   1   5
                75.03          7.21        1.2660    5   2   1
                75.29          1.18        1.2622    3   1   6
                75.30          4.10        1.2621    4   2   4
                78.60          1.05        1.2172    6   1   0
                79.40          6.47        1.2069    2   1   7
                79.41          6.36        1.2068    4   3   3
                81.58          1.54        1.1801    5   2   3
                83.99          3.07        1.1523    0   0   8
                84.00          2.02        1.1521    6   0   4
                85.07          2.34        1.1403    4   3   4
                87.22          3.30        1.1177    5   2   4
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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.