Refractive Index	Mineral	Birefringence
from various sources	no guarantee	from various sources
1.500	Lazurite	0.000
1.500 - 1.520	Bikitaite	0.013
1.500 - 1.610	Lapis Lazuli	0.000
1.502 - 1.519	Petalite	0.012
1.504 - 1.545	Ussingite	0.039 - 0.041
1.508 - 1.511	Leucite	0.001
1.508 - 1.717	Magnesite	0.191
1.509 - 1.525	Scolecite	0.008 - 0.010
1.510 - 1.530	Mellite	0.028
1.510 - 1.532	Poudretteite	0.016 - 0.021
1.512 - 1.522	Leifite	0.010 - 0.011
1.517 - 1.521	Carletonite	0.004
1.517 - 1.525	Pollucite	0.000
1.518 - 1.526	Moonstone	0.007 - 0.008
1.518 - 1.553	Orthoclase	0.005 - 0.012
1.518 - 1.561	Wavellite	0.025 - 0.026
1.520 - 1.680	Ammolite	0.135 - 0.145
1.522 - 1.530	Amazonite	0.008
1.522 - 1.537	Sanidine	0.005 - 0.008
1.522 - 1.578	Cordierite / Iolite	0.005 - 0.017
1.525	Adularia	0.005 - 0.008
1.525	Albite	0.008 - 0.010
1.525 - 1.536	Peristerite	0.008 - 0.010
1.525 - 1.587	Lepidolite	0.029 - 0.038
1.527 - 1.549	Kovdorskite	0.022
1.528 - 1.531	Shomiokite-(Y)	0.003
1.528 - 1.551	Andesine	0.009 - 0.010
1.529 - 1.551	Milarite	0.003
1.529 - 1.677	Witherite	0.148
1.530 - 1.540	Agate	0.004
1.530 - 1.540	Chrysoprase	0.004
1.530 - 1.540	Prasiolite	0.009
1.530 - 1.550	Marialite	0.005 - 0.009
1.530 - 1.685	Aragonite	0.156
1.531 - 1.570	Shortite	0.039
1.533 - 1.552	Oligoclase	0.003 - 0.05
1.534 - 1.540	Tiger's eye	0.009
1.535 - 1.537	Apophyllite	0.002
1.535 - 1.540	Carnelian	0.009
1.539 - 1.545	Amber	0.000
1.540	Jasper	0.009
1.540 - 1.579	Scapolite	0.004 - 0.038
1.542 - 1.551	Cavansite	0.009 - 0.012
1.543 - 1.551	Andesine	0.008 - 0.009
1.543 - 1.554	Amethyst	0.009
1.543 - 1.554	Citrine	0.009
1.543 - 1.554	Quartz	0.009
1.544 - 1.549	Chkalovite	0.005
1.544 - 1.563	Aventurine	0.009
1.545 - 1.560	Charoite	0.007 - 0.009
1.550 - 1.600	Meionite	0.034 - 0.040
1.552 - 1.561	Beryllonite	0.009
1.553 - 1.628	Hambergite	0.072 - 0.074
1.555 - 1.573	Bowenite	?
1.560 - 1.570	Goergeyite	0.024
1.560 - 1.572	Labradorite	0.005 - 0.010
1.560 - 1.572	Oregon Sunstone	0.007 - 0.009
1.560 - 1.580	Brucite	0.020
1.560 - 1.605	Emerald	0.005 - 0.009
1.562 - 1.602	Beryl	0.004 - 0.007
1.563 - 1.59	Norbergite	0.026 - 0.027
1.564 - 1.596	Aquamarine	0.005 - 0.008
1.564 - 1.602	Red Beryl	0.004 - 0.007
1.564 - 1.660	Chalcedony	0.009
1.566 - 1.579	Heliodor	0.004 - 0.007
1.566 - 1.602	Goshenite	0.004 - 0.008
1.570 - 1.590	Augelite	0.014
1.570 - 1.614	Anhydrite	0.042 - 0.044
1.570 - 1.620	Montebrasite	0.020 - 0.050
1.571 - 1.599	Clinochlore	0.005 - 0.011
1.575 - 1.584	Nifontovite	0.009
1.577 - 1.583	Morganite	0.004 - 0.008
1.578 - 1.612	Amblygonite	0.020 - 0.027
1.578 - 1.840	Rhodochrosite	0.218 - 0.220
1.582 - 1.584	Zektzerite	0.002
1.582 - 1.639	Catapleiite	0.036
1.583 - 1.595	Xonotlite	0.012
1.583 - 1.639	Grandidierite	0.037
1.586 - 1.614	Colemanite	0.028
1.587 - 1.597	Bultfonteinite	0.010
1.587 - 1.627	Herderite	0.029 - 0.030
1.590 - 1.596	Ekanite	0.012
1.591 - 1.633	Eudialyte	0.003 - 0.004
1.592 - 1.646	Chondrodite	0.027 - 0.032
1.594 - 1.621	Phosphophyllite	0.021
1.595 - 1.645	Larimar	0.028 - 0.038
1.595 - 1.645	Pectolite	0.028 - 0.038
1.599 - 1.637	Tremolite	0.017 - 0.028