Manganocolumbite
Diffraction data computed using the structure from the paper listed below, 
along with the cell parameters refined from the powder pattern of R040083
      Tarantino S C, Zema M
      American Mineralogist 90 (2005) 1291-1300
      Mixing and ordering behavior in manganocolumbite-ferrocolumbite solid solution:
      A single-crystal X-ray diffraction study
      Sample: RIO n5 Qm=1 from Rio Arriba Co., Globe Mine, U.S.A.

      CELL PARAMETERS:  14.3170  5.7444  5.1089   90.000   90.000   90.000
      SPACE GROUP: Pbcn      

           ATOM        X         Y         Z     OCCUPANCY  ISO(B)
            Fe     0.00000   0.32435   0.25000     0.534     0.624
            Mn     0.00000   0.32435   0.25000     0.457     0.624
            Ti     0.00000   0.32435   0.25000     0.007     0.624
            Sn     0.00000   0.32435   0.25000     0.001     0.624
            Ca     0.00000   0.32435   0.25000     0.001     0.624
            Nb     0.16206   0.17992   0.74297     0.918     0.497
            Ta     0.16206   0.17992   0.74297     0.047     0.497
            Ti     0.16206   0.17992   0.74297     0.028     0.497
            W      0.16206   0.17992   0.74297     0.007     0.497
            O      0.09738   0.10110   0.06330     1.000     0.663
            O      0.08183   0.38420   0.59630     1.000     0.774
            O      0.24378   0.12460   0.41380     1.000     0.632

            X-RAY WAVELENGTH:     1.541838
            BOUNDS ON TWO THETA:    5.0  90.0
            LIMITS IMPOSED ON THE INDICES ARE:  +/- 13 +/-  5 +/-  4
            MAX. ABS. INTENSITY / VOLUME**2:      122.8315729    
            The INTENSITY cut off value is   1.00

               2-THETA      INTENSITY    D-SPACING   H   K   L
                12.36          4.99        7.1585    2   0   0
                16.63          1.54        5.3313    1   1   0
                24.13          7.34        3.6886    1   1   1
                24.25         25.21        3.6708    3   1   0
                24.88          3.73        3.5793    4   0   0
                29.97        100.00        2.9811    3   1   1
                31.14          9.42        2.8722    0   2   0
                35.13         13.15        2.5545    0   0   2
                35.87         13.54        2.5037    0   2   1
                37.70          6.61        2.3862    6   0   0
                40.04          2.85        2.2521    3   0   2
                40.70          5.16        2.2171    3   2   1
                43.14          7.38        2.0967    3   1   2
                44.14          1.26        2.0516    4   2   1
                47.64          7.05        1.9088    0   2   2
                49.67          6.33        1.8354    6   2   0
                50.63          1.75        1.8028    7   1   1
                51.42         12.63        1.7771    3   3   0
                52.48         15.74        1.7437    6   0   2
                53.01         19.83        1.7273    6   2   1
                54.68          1.27        1.6784    3   3   1
                59.87         13.13        1.5448    3   1   3
                62.29          4.83        1.4905    6   2   2
                63.34         10.67        1.4684    9   1   1
                63.51          7.20        1.4648    0   2   3
                63.80         11.49        1.4588    3   3   2
                67.78          5.25        1.3825    0   4   1
                71.81          1.88        1.3145    9   1   2
                74.25          1.43        1.2772    0   0   4
                76.27          1.87        1.2484    6   2   3
                78.11          2.66        1.2236    9   3   0
                79.45          1.10        1.2063    3   1   4
                80.25          5.33        1.1962    6   4   1
                80.50          2.05        1.1931   12   0   0
                82.69          1.11        1.1670    0   2   4
                85.16          3.43        1.1394    9   1   3
                86.41          2.98        1.1261    6   0   4
                87.29          1.40        1.1170    3   5   0
                88.63          4.45        1.1035    9   3   2
                89.21          1.92        1.0978    0   4   3
                89.90          1.68        1.0912    3   5   1
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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.