Cummingtonite Diffraction data computed using the structute from the paper listed below, along with the cell parameters refined from single crystal data of R070267 Fischer K F American Mineralogist 51 (1966) 814-818 A further refinement of the crystal structure of cummingtonite (Mg,Fe)7(Si4O11)2(OH)2 CELL PARAMETERS: 9.5880 18.3210 5.3350 90.000 102.120 90.000 SPACE GROUP: C2/m ATOM X Y Z OCCUPANCY ISO(B) Si 0.28740 0.08420 0.27460 1.000 0.360 Si 0.29770 0.16880 0.78170 1.000 0.430 Mg 0.00000 0.08720 0.50000 0.840 0.380 Fe 0.00000 0.08720 0.50000 0.160 0.380 Mg 0.00000 0.17730 0.00000 0.950 0.360 Fe 0.00000 0.17730 0.00000 0.050 0.360 Mg 0.00000 0.00000 0.00000 0.840 0.300 Fe 0.00000 0.00000 0.00000 0.160 0.300 Mg 0.00000 0.25970 0.50000 0.130 0.790 Fe 0.00000 0.25970 0.50000 0.870 0.790 O 0.11350 0.08740 0.20870 1.000 0.560 O 0.12320 0.17210 0.71930 1.000 0.670 O 0.11340 0.00000 0.70670 1.000 0.810 O 0.37980 0.24600 0.77160 1.000 0.890 O 0.35140 0.13100 0.06590 1.000 0.890 O 0.34880 0.11850 0.55970 1.000 1.010 O 0.34170 0.00000 0.27190 1.000 0.880 X-RAY WAVELENGTH: 1.541838 BOUNDS ON TWO THETA: 0.0 90.0 LIMITS IMPOSED ON THE INDICES ARE: +/- 8 +/- 16 +/- 4 MAX. ABS. INTENSITY / VOLUME**2: 6.108160257 The INTENSITY cut off value is 1.00 2-THETA INTENSITY D-SPACING H K L 9.66 68.80 9.1605 0 2 0 10.60 80.71 8.3453 1 1 0 17.00 14.59 5.2161 0 0 1 17.33 8.18 5.1170 1 3 0 18.29 24.27 4.8493 -1 1 1 19.38 15.60 4.5802 0 4 0 19.58 4.38 4.5328 0 2 1 21.29 22.31 4.1727 2 2 0 21.71 6.74 4.0927 1 1 1 22.69 5.40 3.9194 -2 0 1 22.91 42.05 3.8819 -1 3 1 25.75 50.35 3.4599 1 3 1 25.89 6.18 3.4417 0 4 1 26.11 1.27 3.4128 1 5 0 27.22 63.32 3.2759 2 4 0 28.14 5.57 3.1710 2 0 1 28.99 81.83 3.0803 3 1 0 29.25 3.89 3.0535 0 6 0 29.82 50.63 2.9966 2 2 1 30.01 4.16 2.9779 -2 4 1 30.18 10.58 2.9614 -1 5 1 30.50 1.55 2.9312 -3 1 1 32.18 13.97 2.7818 3 3 0 32.43 100.00 2.7608 1 5 1 33.56 10.68 2.6705 -3 3 1 34.02 50.65 2.6352 0 6 1 34.05 3.93 2.6334 -1 1 2 34.39 4.25 2.6080 0 0 2 34.40 1.44 2.6072 2 4 1 35.07 5.79 2.5585 2 6 0 35.71 68.30 2.5143 -2 0 2 35.80 2.94 2.5084 0 2 2 37.08 2.56 2.4246 -2 2 2 37.33 1.71 2.4088 -2 6 1 37.84 4.78 2.3776 3 5 0 38.67 1.05 2.3283 -4 0 1 38.79 12.18 2.3216 -1 7 1 39.04 24.78 2.3070 -3 5 1 39.34 3.37 2.2901 0 8 0 39.70 1.21 2.2704 4 2 0 39.95 17.17 2.2565 -4 2 1 40.43 15.70 2.2311 -3 1 2 40.59 1.38 2.2228 1 3 2 40.62 11.44 2.2211 1 7 1 40.95 5.11 2.2041 -2 4 2 41.03 48.13 2.1995 2 6 1 42.87 2.89 2.1095 -3 3 2 43.09 23.40 2.0994 2 0 2 43.14 3.46 2.0969 0 8 1 43.37 2.12 2.0863 4 4 0 44.01 4.66 2.0576 2 8 0 44.26 1.74 2.0463 2 2 2 44.32 13.14 2.0437 3 5 1 45.19 3.28 2.0064 3 7 0 45.35 1.69 1.9998 1 5 2 45.60 3.41 1.9893 1 9 0 45.65 1.85 1.9874 4 0 1 45.75 1.78 1.9831 0 6 2 45.89 1.68 1.9773 -2 8 1 46.24 4.74 1.9635 -3 7 1 46.33 11.72 1.9597 -4 0 2 46.80 1.12 1.9410 -2 6 2 47.44 2.96 1.9163 -4 2 2 47.45 2.93 1.9160 -3 5 2 48.23 10.55 1.8869 -1 9 1 48.83 5.08 1.8651 5 1 0 49.00 2.27 1.8591 4 6 0 49.07 2.17 1.8566 2 8 1 49.21 1.71 1.8514 -4 6 1 49.78 2.03 1.8317 1 9 1 50.67 11.37 1.8017 -4 4 2 50.95 2.93 1.7923 5 3 0 52.93 1.21 1.7300 2 6 2 53.15 3.06 1.7234 -2 2 3 53.23 6.93 1.7208 0 8 2 53.65 3.93 1.7082 0 2 3 53.70 7.78 1.7069 -1 3 3 53.75 1.53 1.7053 -3 7 2 54.15 10.41 1.6937 -5 1 2 54.17 3.32 1.6931 -2 8 2 54.50 3.59 1.6836 -5 5 1 54.66 1.02 1.6790 -3 9 1 55.14 39.18 1.6657 4 6 1 55.74 1.04 1.6493 -4 6 2 56.08 13.54 1.6399 1 11 0 56.16 2.42 1.6379 4 8 0 57.63 25.10 1.5995 -1 5 3 58.15 5.68 1.5864 2 10 1 58.19 5.95 1.5855 4 0 2 59.13 6.85 1.5624 6 0 0 59.14 1.76 1.5623 4 2 2 59.70 3.06 1.5488 1 9 2 60.65 18.06 1.5267 0 12 0 60.89 18.03 1.5214 -2 6 3 61.36 7.12 1.5109 0 6 3 61.41 3.45 1.5099 5 5 1 61.81 1.77 1.5010 4 8 1 61.93 6.75 1.4983 4 4 2 62.36 2.98 1.4890 -4 8 2 62.56 7.49 1.4847 -6 0 2 63.23 6.18 1.4706 -1 7 3 63.27 5.03 1.4698 3 11 0 64.11 1.02 1.4526 -3 11 1 64.75 4.00 1.4398 -4 10 1 66.19 1.80 1.4118 -1 11 2 66.23 39.91 1.4112 -6 6 1 66.80 1.93 1.4005 6 2 1 67.21 1.13 1.3929 -2 8 3 67.33 5.98 1.3907 -4 6 3 67.57 13.11 1.3863 5 1 2 68.66 7.49 1.3671 2 6 3 68.73 5.63 1.3658 1 11 2 69.32 2.86 1.3556 5 3 2 70.30 1.61 1.3390 -1 9 3 70.35 1.97 1.3382 -3 11 2 70.51 3.03 1.3356 7 1 0 70.53 1.45 1.3353 -6 6 2 70.53 2.51 1.3352 -5 5 3 70.82 1.54 1.3305 -2 0 4 71.05 3.09 1.3268 -1 1 4 71.62 4.16 1.3176 0 12 2 72.30 1.31 1.3068 -6 8 1 72.40 2.46 1.3053 -5 9 2 72.42 22.11 1.3050 -2 12 2 72.43 1.28 1.3048 -7 1 2 72.48 10.38 1.3040 0 0 4 72.76 1.02 1.2998 -1 3 4 73.14 1.06 1.2940 -3 9 3 73.18 1.40 1.2934 -6 2 3 73.36 1.07 1.2906 6 8 0 73.70 1.13 1.2854 6 6 1 73.95 3.55 1.2817 -7 5 1 73.99 1.30 1.2812 1 9 3 74.12 2.75 1.2792 4 12 0 74.13 1.97 1.2791 -7 3 2 74.22 3.96 1.2777 -2 4 4 74.94 1.44 1.2672 -2 10 3 75.30 2.20 1.2621 4 2 3 75.36 1.07 1.2612 0 10 3 75.65 4.41 1.2572 -4 0 4 77.27 3.19 1.2348 2 12 2 77.54 1.71 1.2312 6 0 2 79.18 1.27 1.2097 2 14 1 79.60 1.86 1.2044 -4 12 2 80.49 3.45 1.1933 2 0 4 80.75 10.31 1.1900 -5 11 2 80.90 1.26 1.1882 -8 2 1 82.19 2.00 1.1728 1 15 1 82.28 1.92 1.1718 8 0 0 84.93 1.07 1.1418 6 6 2 86.37 1.49 1.1265 5 13 0 86.61 1.20 1.1239 -6 0 4 86.95 3.21 1.1205 3 1 4 87.11 2.28 1.1188 7 9 0 87.49 1.36 1.1149 3 13 2 88.45 1.03 1.1053 5 5 3 89.01 5.13 1.0998 4 12 2 ================================================================================ XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.