Breithauptite
Diffraction data computed using the structure from the paper listed below,
along with the cell parameters refined from the powder pattern for R060928
      Wyckoff R W G
      Crystal Structures 1 (1963) 85-237
      Second edition. Interscience Publishers, New York, New York
      Note: ideal nickel arsenide structure

      CELL PARAMETERS:   3.940000   3.940000   5.140000   90.00000   90.00000   120.0000
      SPACE GROUP: P6_3mc
      X-RAY WAVELENGTH:     1.541838
               2-THETA      INTENSITY    D-SPACING   H   K   L
                31.55        100.00        2.8352    1   0   1
                34.94          3.40        2.5674    0   0   2
                44.19         53.79        2.0490    1   0   2
                46.22         51.16        1.9634    1   1   0
                57.03         15.99        1.6141    2   0   1
                59.22          3.95        1.5596    1   1   2
                60.53         12.94        1.5289    1   0   3
                65.85         13.91        1.4176    2   0   2
                73.77          3.41        1.2837    0   0   4
                76.33         11.78        1.2468    2   1   1
                79.39          5.17        1.2063    2   0   3
                84.19         12.24        1.1493    2   1   2
                85.64          6.45        1.1335    3   0   0
                85.64          6.45        1.1335    3   0   0
       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.