Eudialyte, GRR 160, Kola Peninsula 
0.39 mm, E || c   Room Temperature 
1898.1, .086
1890.4, .078
1883.3, .071
1878.4, .065
1866., .06
1841.7, .054
1813.6, .047
1788.4, .042
1771.4, .038
1753.6, .034
1735.8, .031
1719.5, .028
1707.7, .026
1693.6, .024
1680.1, .023
1669.6, .023
1659.8, .024
1642.4, .026
1625.1, .027
1610., .029
1597.8, .031
1586.4, .034
1571.3, .035
1555.4, .038
1541., .041
1525.8, .044
1508.9, .05
1495.9, .054
1484.3, .059
1468.1, .067
1454.2, .074
1444.1, .079
1432.5, .084
1422.5, .088
1414.1, .091
1409.4, .094
1407., .096
1406.2, .098
1405.3, .099
1404.5, .1
1403.7, .101
1402.2, .102
1400.7, .102
1399.9, .101
1398.5, .101
1397.8, .1
1397.1, .099
1395.6, .099
1394.2, .098
1392.7, .097
1390.5, .096
1388.2, .096
1386., .096
1379.2, .097
1371.7, .097
1365.7, .096
1356.1, .095
1347.9, .094
1338.3, .092
1324.2, .089
1314.7, .085
1293.4, .078
1281.7, .074
1264.8, .068
1252.3, .064
1239.8, .06
1225.9, .055
1211.2, .05
1198.6, .047
1181.5, .043
1165.1, .04
1145.7, .038
1126.9, .037
1111.1, .037
1096., .037
1080.1, .038
1059.7, .04
1047.6, .041
1031.7, .042
1016.5, .044
997.6, .045
985.4, .047
955.1, .05
932.3, .053
912.6, .055
900.5, .056
880., .058
860.4, .059
844.6, .059
825., .059
810.7, .058
794.9, .057
777., .055
763.6, .053
747.1, .051
735.8, .051
722.3, .051
711., .051
696.6, .051
682.2, .052
667.1, .054
658.6, .056
651., .059
639.3, .064
626.6, .075
614.1, .094
606.4, .12
598.6, .147
586.5, .196
577.2, .235
569.5, .286
561., .337
548.1, .398
540.8, .431
535., .449
532.5, .454
530.9, .456
529.3, .457
527.7, .458
526.2, .458
524.8, .457
523.3, .456
519.7, .454
517.9, .447
514.3, .432
507.9, .402
503.6, .375
496.2, .337
489.2, .305
481.6, .271
475.2, .252
471.4, .242
468.1, .234
464.6, .23
462.5, .227
461.1, .226
458.1, .226
455.8, .225
452.8, .226
449., .227
445., .229
436.3, .236
427.8, .251
416.5, .287
402.7, .338
387.8, .396
378.7, .444
373.9, .484
371.9, .503
371.9, .517
366.3, .581
361.7, .689
357., .799
352.1, .911
349.1, .994