Refractive Index	Mineral	Birefringence
from various sources	no guarantee	from various sources
1.600 - 1.641	Nephrite	0.020
1.600 - 1.885	Spherocobaltite	0.285
1.601 - 1.620	Pezzotaite	0.008 - 0.011
1.603 - 1.623	Brazilianite	0.019 - 0.021
1.603 - 1.666	Tourmaline	0.006 - 0.080
1.604 - 1.662	Lazulite	0.031 - 0.036
1.605 - 1.640	Imperial Topaz	0.008 - 0.016
1.606 - 1.643	Topaz	0.008 - 0.010
1.606 - 1.672	Edenite	0.020 - 0.025
1.607 - 1.611	Sugilite	0.003 - 0.004
1.607 - 1.628	Bazzite	0.021
1.607 - 1.628	Vlasovite	0.019 - 0.021
1.609 - 1.63	Narsarsukite	0.021 - 0.031
1.609 - 1.644	Inesite	0.035
1.610 - 1.650	Paraiba Tourmaline	0.018 - 0.040
1.610 - 1.650	Turquoise	0.040
1.610 - 1.669	Prehnite	0.020 - 0.035
1.610 - 1.810	Gaspeite	0.220
1.610 - 1.850	Smithsonite	0.225
1.612 - 1.655	Dravite	0.019 - 0.026
1.613	Hsianghualite
1.614 - 1.636	Hemimorphite	0.021 - 0.022
1.614 - 1.655	Actinolite	0.023 - 0.027
1.615 - 1.636	Richterite	0.021
1.615 - 1.650	Elbaite	0.018 - 0.021
1.619 - 1.635	Celestine	0.009 - 0.010
1.621 - 1.675	Datolite	0.044
1.625 - 1.664	Friedelite	0.003
1.625 - 1.675	Clinohumite	0.028 - 0.029
1.627 - 1.641	Danburite	0.006 - 0.009
1.627 - 1.650	Andalusite	0.008 - 0.010
1.628 - 1.650	Apatite	0.003 - 0.007
1.632 - 1.638	Remondite-(Ce)	0.006
1.634 - 1.656	Poldervaartite	0.022
1.636 - 1.648	Barite	0.110 - 0.120
1.638 - 1.671	Eosphorite	0.010 - 0.035
1.640 - 1.653	Jeremejevite	0.009 - 0.017
1.640 - 1.667	Jadeite	0.012 - 0.020
1.640 - 1.828	Allanite	0.013 - 0.026
1.644 - 1.720	Dioptase	0.051 - 0.053
1.649 - 1.691	Childrenite	0.027 - 0.042
1.650 - 1.670	Phenakite	0.015 - 0.017
1.650 - 1.677	Euclase	0.019 - 0.025
1.650 - 1.680	Enstatite	0.007 - 0.020
1.650 - 1.703	Peridot	0.035 - 0.038
1.653 - 1.682	Hiddenite	0.014 - 0.016
1.653 - 1.682	Kunzite	0.014 - 0.016
1.653 - 1.682	Spodumene	0.014 - 0.016
1.653 - 1,684	Sillimanite	0.016 - 0.023
1.655 - 1.999	Malachite	0.254
1.658 - 1.673	Boracite	0.010 - 0.011
1.660 - 1.699	Kornerupine	0.013 - 0.014
1.662 - 1.707	Bustamite	0.013 - 0.018
1.63 - 1.65	Pargasite	0.020
1.633 - 1.875	Siderite	0.240 - 0.242
1.634 - 1.643	Viridine	0.003 - 0.007
1.638 - 1.667	Vaeyrynenite	0.026 - 0.027
1.65 - 1.68	Triplite	0.030
1.663 - 1.694	Olmiite	0.031
1.664 - 1.730	Diopside	0.030
1.665 - 1.684	Lawsonite	0.019 - 0.021
1.665 - 1.712	Sinhalite	0.036 - 0.039
1.67 - 1.73	Sussexite	0.062
1.668 - 1.702	Chrome Diopside	0.029
1.669 - 1.684	Prismatine	0.013
1.670 - 1.734	Clinozoisite	0.005 - 0.015
1.672 - 1.704	Axinite	0.010 - 0.012
1.674 - 1.71	Serandite	0.035 - 0.036
1.675 - 1.740	Legrandite	0.038 - 0.060
1.676 - 1.757	Parisite-(Ce)	0.081
1.677 - 1.718	Dunilite	0.030 - 0.041
1.678 - 1.723	Dumortierite	0.027
1.679 - 1.681	Dolomite	0.179 - 0.181
1.689 - 1.702	Triphylite	0.006 - 0.008
1.690	Rhodizite	0.000
1.690 - 1.705	Tanzanite	0.008 - 0.013
1.690 - 1.724	Willemite	0.028
1.690 - 1.736	Neptunite	0.029 - 0.045
1.692 - 1.739	Phosphosiderite	0.046