Chrysoberyl
Diffraction data computed using the structure from the paper listed below, 
along with the cell parameters refined from the powder pattern of R040073
      Hazen R M, Finger L W
      Physics and Chemistry of Minerals 14 (1987) 426-434
      High-temperature crystal chemistry of phenakite (Be2SiO4) and
      Chrysoberyl (BeAl2O4)
      Sample: T = 25 C

      CELL PARAMETERS:   4.4286  9.4095  5.4789   90.000   90.000   90.000
      SPACE GROUP: Pbnm      

           ATOM        X         Y         Z     OCCUPANCY  ISO(B)
            Al     0.00000   0.00000   0.00000     1.000     0.320
            Al     0.99490   0.27306   0.25000     1.000     0.200
            Be     0.43330   0.09290   0.25000     1.000     0.440
            O      0.78740   0.09010   0.25000     1.000     0.350
            O      0.24220   0.43300   0.25000     1.000     0.360
            O      0.25680   0.16310   0.01540     1.000     0.380

            X-RAY WAVELENGTH:     1.541838
            BOUNDS ON TWO THETA:    5.0  90.0
            LIMITS IMPOSED ON THE INDICES ARE:  +/-  4 +/-  8 +/-  5
            MAX. ABS. INTENSITY / VOLUME**2:      7.608246134    
            The INTENSITY cut off value is   1.00

               2-THETA      INTENSITY    D-SPACING   H   K   L
                18.86          4.59        4.7048    0   2   0
                22.19         48.82        4.0070    1   1   0
                24.95          1.66        3.5694    0   2   1
                25.87          2.67        3.4442    1   0   1
                27.58         93.73        3.2343    1   1   1
                27.66          1.90        3.2247    1   2   0
                32.21          1.91        2.7791    1   2   1
                32.69          1.05        2.7394    0   0   2
                35.06         57.16        2.5596    1   3   0
                38.01          9.32        2.3674    0   2   2
                38.26          2.97        2.3524    0   4   0
                38.83         34.24        2.3190    1   3   1
                39.86         50.97        2.2615    1   1   2
                41.79          3.63        2.1616    0   4   1
                41.91          1.95        2.1554    2   1   0
                43.34         95.13        2.0878    1   2   2
                43.56         49.14        2.0775    1   4   0
                45.21          3.83        2.0058    2   1   1
                48.37          1.63        1.8816    2   2   1
                48.69          7.27        1.8703    1   3   2
                52.86          1.20        1.7320    1   5   0
                55.28         12.52        1.6618    1   1   3
                55.66          7.71        1.6515    1   5   1
                56.94        100.00        1.6172    2   2   2
                57.13         42.11        1.6124    2   4   0
                58.04          1.18        1.5891    1   2   3
                59.79          7.96        1.5468    2   4   1
                61.50          7.47        1.5077    0   6   1
                62.47          8.40        1.4867    1   3   3
                63.55         20.27        1.4640    1   5   2
                63.82          1.81        1.4584    3   1   0
                64.61          2.71        1.4426    0   4   3
                66.33          4.43        1.4093    3   1   1
                67.39          1.45        1.3895    2   4   2
                67.52          1.22        1.3872    2   5   1
                68.50         26.45        1.3697    0   0   4
                69.00         41.05        1.3610    0   6   2
                70.51          5.69        1.3357    3   3   0
                72.89          9.63        1.2977    3   3   1
                73.00          2.90        1.2961    1   1   4
                73.58         10.94        1.2873    3   1   2
                73.65          9.49        1.2863    1   7   0
                75.68          2.76        1.2567    1   5   3
                75.97         12.35        1.2526    3   2   2
                76.13          5.34        1.2504    3   4   0
                76.43          1.01        1.2462    2   6   1
                79.26          1.48        1.2087    2   4   3
                79.34          9.13        1.2077    1   3   4
                80.77          2.77        1.1898    0   6   3
                81.28          1.64        1.1837    0   4   4
                84.78          6.13        1.1435    1   4   4
                85.14          2.04        1.1396    3   1   3
                85.40          2.33        1.1368    1   8   0
                85.45          1.23        1.1362    3   5   1
                88.26          9.45        1.1071    4   0   0
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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.