 |
Biaxial Minerals sorted by Index of Refraction |
|
|
Biaxial Minerals sorted by Index of Refraction |
( Bold - Valid Mineral Name)
(* - Mineral Name is Not IMA Approved)
(! - New Dana Classification Number Has Been Changed or Added)
(? - IMA Discredited Mineral Species Name)
(# - Grandfathered as valid)
Pages: [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ] [ 8 ] [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ 13 ] [ 14 ] [ 15 ] [ 16 ] [ 17 ] [ 18 ] [ 19 ] [ 20 ] [ 21 ] [ 22 ] [ 23 ] [ 24 ] Optical Help
| Mineral Name | α | β | γ | Sign | 2V | Bire | Pleo- chroic |
Dispersion |
| Ferrogedrite | 1.642 to 1.694 | 1.649 to 1.71 | 1.661 to 1.722 | B- | 82 | .0190 to .0280 | No | |
| Pellyite | 1.643 | 1.645 | 1.649 | B+ | 47 | .0060 | No | very strong, r > v |
| Obertiite ! | 1.643 | 1.657 | 1.67 | B- | 81 | .0270 | Yes | dispersion not observed |
| Jahnsite-(CaMnMn) | 1.643 | 1.659 | 1.671 | B- | 80-81 | .0280 | No | |
| Ranunculite | 1.643 | 1.664 | 1.67 | B- | 56 | .0270 | Yes | |
| Uranophane # | 1.643 | 1.666 | 1.669 | B- | 32-45 | .0260 | Yes | relatively strong |
| Clintonite # | 1.643 to 1.648 | 1.655 to 1.662 | 1.655 to 1.663 | B- | 2-40 | .0120 to .0150 | Yes | none |
| Leucosphenite # | 1.643 to 1.649 | 1.657 to 1.664 | 1.681 to 1.691 | B+ | 77 | .0380 to .0420 | Yes | weak, r > v |
| Reddingite # | 1.643 to 1.658 | 1.648 to 1.664 | 1.674 to 1.685 | B+ | 41-65 | .0310 | No | strong, r > v |
| Messelite # | 1.644 | 1.653 | 1.68 | B+ | 20-35 | .0360 | No | |
| Weilite | 1.644 | 1.67 | 1.688 | B- | 82 | .0440 | No | |
| Holdawayite | 1.644 | 1.719 | 1.721 | B- | 12-18 | .0770 | No | |
| Yuksporite # | 1.644 | 1.66 | B | 46-76 | .0160 | Yes | ||
| Koninckite # | 1.645 | 1.656 | 1.656 | B | .0110 | No | ||
| Lithiomarsturite | 1.645 | 1.66 | 1.666 | B- | 59.9-64 | .0210 | No | |
| Plancheite # | 1.645 | 1.66 | 1.715 | B+ | 0-20 | .0700 | Yes | |
| Samuelsonite | 1.645 to 1.648 | 1.65 to 1.655 | 1.655 to 1.667 | B+ | 70-85 | .0100 to .0190 | No | r < v weak |
| Mosandrite # | 1.646 | 1.649 | 1.658 | B+ | 43-87 | .0120 | No | r > v strong |
| Boehmite # | 1.646 | 1.652 | 1.661 | B+ | 80 | .0150 | Yes | |
| Korobitsynite ! | 1.646 | 1.654 | 1.763 | B+ | 30 | .1170 | Yes | |
| Roweite # | 1.646 | 1.658 | 1.66 | B- | 28 | .0140 | No | |
| Pennantite # | 1.646 | 1.661 | 1.661 | B- | 0 | .0150 | No | |
| Gonyerite # | 1.646 | 1.664 | 1.664 | B- | 0 | .0180 | Yes | |
| Cobaltkoritnigite | 1.646 | 1.668 | 1.705 | B+ | 78 | .0590 | No | |
| Eriochalcite # | 1.646 | 1.685 | 1.745 | B+ | 75 | .0990 | No | |
| Taneyamalite | 1.646 to 1.697 | 1.664 to 1.72 | 1.676 to 1.732 | B- | 70 | .0300 to .0350 | Yes | |
| Kilchoanite | 1.647 | 1.649 | 1.65 | B+ | 60 | .0030 | Yes | r > v |
| Gjerdingenite-Na ! | 1.647 | 1.653 | 1.755 | B+ | 25 | .1080 | Yes | dispersion not observed |
| Hureaulite # | 1.647 | 1.654 | 1.66 | B- | 75 | .0130 | Yes | r < v very strong |
| George-ericksenite ! | 1.647 | 1.674 | 1.704 | B+ | 88 | .0570 | Yes | |
| Sclarite | 1.648 | 1.664 | 1.702 | B+ | 63.4-67 | .0540 | No | |
| Metakottigite | 1.648 | 1.68 | 1.716 | B+ | 93 | .0680 | Yes | |
| 1.648 to 1.658 | 1.655 to 1.662 | 1.662 to 1.671 | B+ | 80-90 | .0140 | Yes | relatively strong | |
| Spodumene # | 1.648 to 1.661 | 1.655 to 1.67 | 1.662 to 1.679 | B+ | 54-69 | .0140 to .0180 | Yes | weak, r < v |
| Natrochalcite # | 1.649 | 1.655 | 1.714 | B+ | 36.8 | .0650 | No | r < v strong |
| Vuoriyarvite-K ! | 1.649 | 1.655 | 1.759 | B+ | 20-28 | .1100 | No | weak, r < v |
| Maleevite ! | 1.649 | 1.656 | 1.656 | B- | 5 | .0070 | No | |
| Tsepinite-Sr ! | 1.649 | 1.657 | 1.77 | B+ | 20 | .1210 | Yes | very weak r,v |
| Upalite | 1.649 | 1.666 | 1.676 | B- | 74 | .0270 | No | |
| Childrenite # | 1.649 | 1.683 | 1.691 | B- | 40-45 | .0420 | Yes | strong, r < v |
| Ohmilite | 1.649 | 1.715 | B | .0660 | No | |||
| Vladimirite # | 1.65 | 1.654 to 1.656 | 1.661 | B- | 70 | .0110 | No | |
| Triplite # | 1.65 | 1.66 | 1.68 | B+ | 70-90 | .0300 | No | relatively strong |
| Paraspurrite | 1.65 | 1.672 | 1.677 | B- | 47 | .0270 | No | |
| Francoisite-(Nd) | 1.65 | 1.74 | 1.75 | B- | 35 | .1000 | No | |
| Vanuralite | 1.65 | 1.85 | 1.9 | B- | 44 | .2500 | No | |
| Nyboite | 1.65 | 1.67 | B- | .0200 | Yes | Calculated index values | ||
| Otwayite | 1.65 | 1.72 | B | .0700 | Yes | |||
| Soddyite # | 1.65 to 1.654 | 1.685 | 1.699 to 1.715 | B- | 85 | .0490 to .0610 | Yes | |
| Attakolite # | 1.65 to 1.655 | 1.654 to 1.664 | 1.661 to 1.675 | B+ | 75-84 | .0110 to .0200 | No | |
| Enstatite # | 1.65 to 1.668 | 1.652 to 1.673 | 1.659 to 1.679 | B+ | 54-90 | .0090 to .0110 | No | weak, r < v |
| Greenalite # | 1.65 to 1.675 | 1.674 | 1.674 | B+ | 0 | .0240 | Yes | |
| 1.65 to 1.71 | 1.85 to 1.92 | 1.9 to 1.95 | B- | 44 | .2500 | Yes | r < v weak | |
| Yanomamite | 1.65 | B+ | 55-76 | No | ||||
| Arrojadite-(BaFe) ! | 1.65 | B-+ | Yes | |||||
| Clinoenstatite # | 1.651 | 1.654 | 1.66 | B+ | 53 | .0090 | No | |
| Bityite # | 1.651 | 1.659 | 1.661 | B- | 35-52 | .0100 | No | |
| Gotzenite # | 1.651 to 1.662 | 1.653 to 1.665 | 1.659 to 1.672 | B+ | 38-74 | .0080 to .0100 | Yes | r > v strong |
| Kotoite # | 1.652 | 1.653 | 1.673 | B+ | 21 | .0210 | No | |
| Euclase # | 1.652 | 1.655 | 1.671 | B+ | 50 | .0190 | Yes | none |
| Baghdadite | 1.652 | 1.658 | 1.67 | B+ | 72 | .0180 | No | |
| Arfvedsonite # | 1.652 to 1.699 | 1.66 to 1.705 | 1.666 to 1.708 | B- | 30-70 | .0140 | Yes | r > v strong |
| Ludlamite # | 1.653 | 1.675 | 1.697 | B+ | 82 | .0440 | No | r > v |
| Ankinovichite ! | 1.653 | 1.677 | 1.706 | B+ | 86 | .0530 | Yes | r < v strong |
| Synchysite-(Y) | 1.653 | 1.73 | B | .0770 | No | |||
| Sillimanite # | 1.653 to 1.661 | 1.654 to 1.67 | 1.669 to 1.684 | B+ | 20-30 | .0160 to .0230 | Yes | strong, r > v |
| Magnesiohastingsite # | 1.653 to 1.67 | 1.661 to 1.69 | 1.669 to 1.7 | B- | 60-90 | .0160 to .0300 | Yes | weak, r > v |
| Potassicpargasite ! | 1.654 | 1.664 | 1.67 | B- | 79 | .0160 | Yes | dispersion not observed |
| Alumino-magnesiotaramite ! | 1.654 | 1.666 | 1.671 | B- | 74 | .0170 | Yes | r << v extreme |
| Lulzacite ! | 1.654 | 1.674 | 1.684 | B- | 45-65 | .0300 | Yes | r < v distinct |
| Kornite | 1.654 | 1.675 | 1.696 | B- | 88-92 | .0420 | Yes | |
| Calcioancylite-(Ce) # | 1.654 | 1.733 | 1.772 | B- | 60-70 | .1180 | No | r < v |
| Cuprosklodowskite # | 1.654 to 1.655 | 1.664 to 1.667 | 1.664 to 1.667 | B- | 0-5 | .0100 to .0120 | No | |
| Jadeite # | 1.654 to 1.673 | 1.659 to 1.679 | 1.667 to 1.693 | B+ | 70-80 | .0130 to .0200 | Yes | r < v |
| Gerstmannite | 1.655 | 1.657 | 1.678 | B- | 50-60 | .0230 | No | |
| Aurichalcite # | 1.655 | 1.74 | 1.744 | B- | 1-4 | .0890 | Yes | relatively strong |
| Malachite # | 1.655 | 1.875 | 1.909 | B- | 43 | .2540 | Yes | relatively weak |
| Paraotwayite | 1.655 | 1.705 | B | .0500 | No | |||
| Junitoite | 1.656 | 1.664 | 1.672 | B | 86 | .0160 | No | |
| Geminite | 1.656 | 1.692 | 1.77 | B+ | 75 | .1140 | Yes | weak, r > v |
| Kupletskite # | 1.656 | 1.699 | 1.731 | B- | 79 | .0750 | No | |
| Kuliokite-(Y) | 1.656 | 1.7 | 1.703 | B- | 19-29 | .0470 | No | r > v |
| Paratsepinite-Na ! | 1.657 | 1.666 | 1.765 | B+ | 19-31 | .1080 | No | |
| Manganosegelerite | 1.657 | 1.668 | 1.691 | B+ | 70-75 | .0340 | Yes | r < v marked |
| Manganokukisvumite ! | 1.657 | 1.741 to 1.747 | 1.789 to 1.795 | B- | 70 | .1320 to .1380 | Yes | dispersion not observed |
| Bouazzerite ! | 1.657 | 1.66 | B | .0030 | No | |||
| Jungite | 1.658 | 1.658 | 1.664 | B- | 60 | .0060 | No | r < v strong |
| 1.658 | 1.669 | 1.67 | B- | 25 | .0120 | No | ||
| Magnesioastrophyllite | 1.658 | 1.687 | 1.71 | B- | 81.5-83 | .0520 | Yes | |
| Alvanite | 1.658 | 1.714 | B- | 80-85 | .0560 | No | ||
| Tsepinite-Na ! | 1.658 to 1.661 | 1.668 | 1.77 | B+ | 19-31 | .1120 | Yes | |
| Boracite # | 1.658 to 1.6622 | 1.662 to 1.667 | 1.668 to 1.673 | B+ | 82.5 | .0100 to .0108 | No | |
| Arrojadite-(PbFe) ! | 1.6585 | 1.66 | 1.668 | B+ | 57.5 | .0095 | Yes | r > v |
| Bergslagite | 1.659 | 1.681 | 1.694 | B- | 70 | .0350 | No | |
| Lautenthalite | 1.659 | 1.703 | 1.732 | B- | 78-79 | .0730 | No | |
| Dovyrenite ! | 1.659 | to 1.66 | 1.676 | B+ | 30 | .0170 | No | |
| Dumortierite # | 1.659 to 1.678 | 1.684 to 1.691 | 1.686 to 1.692 | B- | 20-52 | .0270 | Yes | r > v or r < v |
| Magnesio-arfvedsonite # | 1.66 | 1.662 | 1.664 | B- | 33-40 | .0040 | No | |
| Davreuxite # | 1.66 | 1.684 | 1.69 | B- | 48 | .0300 | No | |
| Davanite | 1.66 | 1.684 | 1.69 | B- | .0300 | No |