Check out the video atlas of minerals in thin section introduction page for some background on how these videos were prepared and processed, and for additional useful information on the included table content, the search tab, and other user-adjustable features. There is also an accompanying illustration to assist viewers with determining 2V° values from the BxA or optic axis figures in the “optic figures” videos.
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| mineral | PPL (lower polar rotation) |
PPL (stage rotation) |
XP (stage rotation) |
optic figure (stage rotation) |
|---|---|---|---|---|
| melilite (FKM-56): Na-rich melilite (0.36 Na apfu; 0.46 Mg apfu) in haüyne melilitolite (“okaite”), with calcite, phlogopite trioctahedral mica, apatite and magnetite |
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| melilite (FKM-114): Na-rich melilite (0.36 Na apfu; 0.53 Mg apfu) in olivine melilitite, with forsterite olivine, diopside clinopyroxene and nepheline |
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| åkermanite (FKM-262): åkermanite-dominant (0.23 Al apfu; 0.67 Mg apfu; 0.25 Na apfu) melilite in alkaline ultramafic intrusive, with diopside clinopyroxene |
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| gehlenite (FKM-271): Fe-rich gehlenite-dominant (0.30 Fe3+ apfu) melilite in pyrometamorphic sanidinite facies phosphatic metacarbonate, with apatite and brown cebollite (note: thin section is slightly thick) |
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| “blue melilite” (FKM-384): “blue melilite” (Fe2+-Fe3+ IVCT?; zoned with “yellow melilite”) in sanidinite-facies paralava (further characterization of melilite and associated minerals pending) |
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| “yellow melilite” (FKM-384): “yellow melilite” (Fe3+-bearing?) in sanidinite-facies paralava (further characterization of melilite and associated minerals pending) |
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| hardystonite (FKM-303): zoned hardystonite (main: 0.09 [Al+Mg+Fe] apfu & 0.06 Na apfu; patchy: 0.05 [Sr+Pb] apfu) in high-grade Mn-Zn metasomatite, with bustamite and andradite garnet |
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| bertrandite (FKM-209): open-space filling bertrandite sheaves in granite pegmatite, with fluorapatite |
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| bertrandite (FKM-291): bertrandite in skarn, with quartz and carbonate |
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| tinzenite (FKM-185): tinzenite (axinite group) in metasomatized meta-Mn-exhalite, with quartz |
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| lawsonite (FKM-109): lawsonite in blueschist facies metabasite, with garnet, glaucophane amphibole, white mica and chlorite |
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| niocalite (FKM-57): niocalite in sövite carbonatite, with calcite and apatite |
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| hiortdahlite (FKM-315): hiortdahlite in metamorposed agpaitic syenite, with fluorite, alkali feldspar (primarily microcline) and zoned omphacite/aegirine-augite clinopyroxene |
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| mosandrite-(Ce) (FKM-65): mosandrite-(Ce) in metamorposed agpaitic syenite, with microcline K-feldspar, eudialyte and fluoro-richterite amphibole |
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| mosandrite-(Ce) (FKM-145): mosandrite-(Ce) in agpaitic nepheline syenite, with arfvedsonite amphibole, aegirine clinopyroxene, eudialyte and nepheline |
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| lamprophyllite (FKM-17): lamprophyllite in nepheline syenite, with aegirine, nepheline and microcline |
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| lamprophyllite (FKM-320): lamprophyllite in nepheline syenite, with potassic-arfvedsonite, alkali feldspar and eudialyte |
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| melanotekite (FKM-86): melanotekite in high grade calcareous Ba-Mn-metasomatite, with phlogopite trioctahedral mica |
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| strontioruizite (FKM-173): orange strontioruizite (1.82 Sr apfu) in Mn-metasomatite, with aluminosugilite/sugilite ss, quartz, pectolite and fine-grained aegirine. |
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| prismatine (FKM-59): prismatine (kornerupine group) in granulite facies B-bearing metapelite, with plagioclase feldspar and tourmaline |
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| allanite-(Ce) (FKM-131): allanite-(Ce) (epidote group) in calc-silicate REE-U metasomatite, with andradite garnet |
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| [Cr+V]-bearing allanite-(Ce) (FKM-332): epidote-group allanite-(Ce) with up to 0.39 [M1+M3]Cr apfu and up to 0.11 [M1+M3]V apfu in alkali-chloride metasomatized low-grade meta-“oil shale”, with tremolite, quartz and alkali feldspars |
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| ferriallanite-(Ce) (FKM-89): anomalously low-2V° ferriallanite-(Ce) (epidote group) in REE-metasomatite, with cerite-(Ce) and tremolite amphibole |
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| dollaseite-(Ce) (FKM-188): anomalously high-2V° dollaseite-(Ce) (1.69 [M1+M3]Mg apfu; epidote group) in calcareous REE-metasomatite, with tremolite amphibole and calcite |
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| epidote (FKM-4): epidote (0.50 Fe3+ apfu; epidote group) in blueschist, with glaucophane amphibole |
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| epidote (FKM-44): zoned epidote (0.53 Fe3+ apfu core; 0.99 Fe3+ apfu rim; epidote group) in greenschist facies Na-Ca metasomatite, with quartz and chlorite |
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| hancockite (FKM-88): hancockite (epidote group) in high grade calcareous Zn-Mn-Pb-Ba metasomatite, with barite |
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| piemontite (FKM-2): Sr-bearing (0.36 Sr apfu) piemontite (epidote group) in meta-Mn-exhalite, with titanite and quartz |
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| piemontite/Mn-rich epidote (FKM-341): zoned piemontite to epidote (0.52 Mn3+ apfu & 0.31 Fe3+ apfu core; 0.50 Fe3+ apfu & 0.32 Mn3+ apfu rim; epidote group) in whiteschist-associated Mn-bearing calc-silicate, with calcic amphibole |
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| clinozoisite (FKM-168): clinozoisite (0.32 Fe3+ apfu; epidote group) in calc-silicate, with quartz |
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| zoisite (FKM-1): zoisite (“tanzanite”; 1.00 M3Al apfu) in high grade calc-silicate, with grossular garnet, quartz and calcite |
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| zoisite (FKM-68): Cr-bearing zoisite (0.01 Cr apfu in high grade meta-gabbroid, with pargasite amphibole and corundum |
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| zoisite (FKM-290): Cr-bearing zoisite (0.02 Cr apfu in high grade meta-gabbroid |
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| shuiskite-(Mg) (FKM-316): zoned shuiskite-(Mg) (est. 0.31 XCr apfu & 0.62 YCr apfu) to Cr-bearing (est. 0.35 XCr apfu & 1.04 YCr apfu) pumpellyite-(Mg) in altered chromatite, with zoned uvarovite/Cr-bearing grossular garnet |
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| vesuvianite (FKM-110): anomalously biaxial vesuvianite in high grade calc-silicate skarn, with fine-grained undifferentiated alteration minerals |
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| vesuvianite (FKM-263): vesuvianite in Al-rich “calc-skarnoid”, with hibonite and calcite |
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| manganvesuvianite (FKM-334): Cu-bearing manganvesuvianite in Mn-metasomatite, with opaque hausmannite; (note: colorless portion of sample is epoxy) |
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| ganomalite (FKM-324): anomalously B(+) ganomalite in high grade calcareous Mn-metasomatite, with phlogopite, calcite and garnet(?) |
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| yoshimuraite (FKM-299): yoshimuraite in meta-Mn-metasomatite, with “rhodonite”, hjalmarite amphibole, and quartz |
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| ardennite-(As) (FKM-372): ardennite-(As) in quartz vein cutting Mn-bearing schist, with quartz |
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| benitoite (FKM-244): benitoite in serpentine-hosted natrolite veins, with neptunite and natrolite(?) |
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| beryl (FKM-288): beryl in granite pegmatite-associated Be-F metasomatite, with phenakite, fluorite and biotite |
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| cordierite (FKM-23): uncommonly B(+) & weakly pleochroic cordierite (1.67 Mg apfu) in granulite facies metapelite, with garnet and rutile |
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| cordierite (FKM-46): uncommonly B(+) cordierite partially altered to pinite in granulite facies B-bearing metapelite, with garnet and K-feldspar |
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| baratovite (FKM-278): baratovite in alkali granite, with aegirine, albite and quartz |
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| dravite (FKM-292): dravite (2.58 YMg apfu) in tourmaline-bearing mica schist, with muscovite dioctahedral mica |
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| foitite (FKM-70): foitite tourmaline in a B-bearing meta-“advanced argillic” metasomatite, with dumortierite and illite? |
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| uvite (FKM-119): uvite (OH-dominant) tourmaline (anomalously biaxial) in Mg-metasomatic talc schist, with talc |
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| uvite (FKM-210): uvite tourmaline in Mg-metasomatite, with magnesite |
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| oxy-schorl (FKM-85): zoned oxy-schorl tourmaline in granite, with quartz |
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| oxy-schorl/”oxy-olenite” (FKM-281): oxy-schorl with thin near-rim “oxy-olenite” tourmaline in granite, with quartz and orthoclase “perthite” feldspar |
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| oxy-dravite (FKM-102): zoned oxy-dravite (core) to dravite (rim) tourmaline in muscovite biotite mica schist |
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| oxy-dravite (FKM-166): Cr-bearing (0.57 to 0.94 Cr apfu) green oxy-dravite tourmaline in metasomatic fuchsite schist, with quartz and Cr-bearing muscovite dioctahedral mica |
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| oxy-chromium-dravite (FKM-276): bright green oxy-chromium-dravite (4.68 to 5.18 [Y+Z]Cr apfu; [Y+Z]Cr/[Y+Z](Cr+Al) = 0.72 to 0.79) tourmaline in granulite facies metasomatic calcareous meta-evaporite, with quartz and Cr-bearing tremolite amphibole (100X) |
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| povondraite (FKM-71): zoned povondraite to “K-povondraite” tourmaline in meta-evaporite, with alkali feldspar and hydromagnesite? |
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| osumilite (FKM-240): anomalously biaxial osumilite (0.95 Fe2+ apfu; 0.85 Mg apfu) in rhyodacite(?), with tridymite and/or cristobalite |
anomalously biaxial with a mod-low 2V°, but the optic sign was inconclusive & the figure was of too low quality to be useful here | |||
| aluminosugilite (FKM-173): pale lilac aluminosugilite cores (1.10 MAl apfu; 0.57 MMn3+ apfu) rimmed by deeper lilac sugilite (1.11 MFe3+ apfu; 0.72 MMn3+ apfu) in Mn-metasomatite, with quartz, pectolite and fine-grained intergrown amphibole+aegirine. |
presumably U(-), but the birefringence was too low to obtain a figure | |||
| eudialyte (FKM-77): zoned eudialyte in kakortokite, with albite plagioclase |
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| eudialyte (FKM-130): eudialyte in nepheline syenite, with aegirine clinopyroxene and alkali feldspar |
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| eudialyte (FKM-145): eudialyte in agpaitic nepheline syenite, with amphibole, alkali feldspar and nepheline |
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| ferrokentbrooksite (FKM-207): weakly pleochroic and anomalously slightly biaxial irregularly-zoned ferrokentbrooksite to eudialyte (M2Fe2+ > M2Mn2+; 0.76 to 0.17 M3Nb apfu) in agpaitic nepheline syenite, with albite and nepheline |
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| titantaramellite (FKM-53b): titantaramellite in Ba-metasomatite, with quartz, gillespite, actinolite and alforsite |
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| cerchiaraite-(Fe) (FKM-53b): strongly pleochroic zoned cerchiaraite-(Fe) to near cerchiaraite-(Al) in Ba-metasomatite, with sanbornite, gillespite, actinolite and quartz |
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| muirite (FKM-344): muirite in Ba-metasomatite, with sanbornite, celsian and quartz |
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single chain inosilicates in thin section
double chain and more complex inosilicates in thin section
phyllosilicates in thin section
tectosilicates and miscellaneous silicates in thin section