double chain and more complex inosilicates in thin section

 

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)
anthophyllite (FKM-186):
anthophyllite amphibole in meta-blackwall, with phlogopite
“sodic-gedrite” (FKM-11):
“sodic-gedrite” (0.58 XIINa apfu) amphibole in granulite facies meta-blackwall, with sapphirine and phlogopite mica
proto-ferro-suenoite
(FKM-190): proto-ferro-suenoite (3.14 to 3.91 VIFe2+ apfu; 1.58 to 1.87 VIIIMn2+ apfu) amphibole (formerly “proto-mangano-ferro-anthophyllite”) in high grade meta-Mn-metasomatite, with rhodochrosite, quartz, spessartine garnet and pyroxmangite
cummingtonite (FKM-419):
Mn-bearing cummingtonite (0.32 VIIIMn2+ apfu) amphibole, in Mn-enriched Fe-metasomatite, with opaques pyrrhotite and magnetite
clino-suenoite (FKM-122):
anomalously B(-) clino-suenoite (4.91 VIMg apfu; 1.25 VIIIMn2+ apfu) amphibole (formerly “tirodite” or “manganocummingtonite”) in Mn-rich pod in granulite facies metasomatized meta-evaporite, with donpeacorite orthopyroxene
clino-ferro-suenoite
(FKM-94): clino-ferro-suenoite (3.08 VIFe2+ apfu; 1.34 VIIIMn2+ apfu) amphibole (formerly “dannemorite” or “manganogrunerite”) in granulite facies metasomatized-Mn-Zn-Pb exhalite, with Fe-bearing pyroxmangite and Fe-bearing spessartine garnet
tremolite (FKM-26):
V-bearing (0.31 V apfu) tremolite-magnesio-hornblende near-boundary composition amphibole in high grade calc-silicate, with calcite, quartz and diopside clinopyroxene
tremolite (FKM-123):
lilac tremolite (“hexagonite”) amphibole in high grade calcareous meta-evaporite
tremolite (FKM-276):
Cr-bearing tremolite (0.03 to 0.06 Cr apfu) amphibole in granulite facies metasomatic calcareous meta-evaporite, with quartz and oxy-chromium-dravite tourmaline
tremolite (FKM-368):
tremolite amphibole in calcareous REE-metasomatite, with minor dollaseite-(Ce)
actinolite (FKM-95):
actinolite (2.36 Fe2+ apfu) amphibole in greenschist facies meta-BIF, with magnetite, quartz and calcite
magnesio-hornblende
(FKM-161): Mn-bearing magnesio-hornblende (3.86 VIMg apfu; 0.23 VIIIMn2+ apfu) amphibole in amphibolite facies Ca-metasomatite, with quartz
tschermakite (FKM-24):
tschermakite (2.97 VIMg apfu; 1.04 VIAl apfu; 0.94 Fe3+ apfu) amphibole in high grade amphibolite, with anorthite plagioclase feldspar
pargasite (FKM-11):
pargasite amphibole in granulite facies meta-blackwall, with sapphirine and “sodic-gedrite” amphibole
pargasite (FKM-16):
pargasite (4.06 Mg apfu) amphibole in metasomatic amphibolite, with chrysoberyl
pargasite (FKM-68):
Cr-bearing pargasite (0.07 Cr apfu) amphibole in high grade meta-gabbroid, with zoisite and corundum
pargasite (FKM-290):
Cr-bearing pargasite (0.13 Cr apfu amphibole in high grade meta-gabbroid, with epidote, clinochlore chlorite, Cr-bearing spinel and zoisite
ferro-pargasite (FKM-401):
ferro-pargasite amphibole in Be-enriched Fe metasomatite, with biotite
mangani-pargasite (FKM-387):
mangani-pargasite amphibole in Mn metasomatite, with calcite and hausmannite
magnesio-hastingsite
(FKM-96): potassian magnesio-hastingsite (0.32 K apfu; 2.22 VIMg apfu; 0.80 Fe3+ apfu; 0.38 Ti apfu) amphibole in granulite facies meta-tonalite, with plagioclase
magnesio-hastingsite
(FKM-264): magnesio-hastingsite (3.70 VIMg apfu; 0.75 Fe3+ apfu) amphibole in alkaline ultramafic intrusive, with calcite
magnesio-hastingsite
(FKM-265): magnesio-hastingsite (3.47 to 3.80 VIMg apfu; 0.71 Fe3+ apfu; 0.02 Cr apfu) amphibole in alkaline ultramafic intrusive, with calcite and diopside
potassic-magnesio-hastingsite
(FKM-21): potassic-magnesio-hastingsite amphibole in K-Cl-Fe metasomatite, with magnetite
hastingsite (FKM-33):
K- and Cl-bearing (0.39 K apfu; 0.26 Cl apfu) hastingsite amphibole in high grade K-Cl-Fe metasomatite, with biotite mica
joesmithite (FKM-408):
joesmithite amphibole in meta-Mn-metasomatite, with forsterite, calcite, and minor phlogopite, hematite and phosphatian hedyphane
ferri-kaersutite (FKM-49):
zoned ferri-kaersutite (yellow/brown core) to magnesio-hastingsite (yellow/green rim) amphibole in nepheline syenite, with clinopyroxene, apatite, titanite, plagioclase and an opaque oxide
ferri-kaersutite (FKM-251):
potassian ferri-kaersutite amphibole in essexite, with biotite, apatite, titanite, plagioclase and nepheline
winchite (FKM-74):
zoned winchite-richterite-actinolite near-boundary composition amphibole in carbonatite-associated K-metasomatite, with diopside clinopyroxene, microcline K-feldspar and calcite
[winchite]-[katophorite] join (NaCa)-amphibole (FKM-394):
Cr-bearing (up to 0.13 Cr apfu) (NaCa)-amphibole along the winchite-katophorite join in sodic-amphibole jadeitite, with eckermannite (near glaucophane boundary)
video pending video pending video pending video pending
barroisite (FKM-34):
zoned barroisite to taramite amphibole in eclogite facies metabasite, with garnet, rutile, quartz and zoisite
fluoro-richterite (FKM-27):
fluoro-richterite amphibole in metamorposed agpaitic syenite, with eudialyte, K-feldspar, aegirine clinopyroxene and fluorite
fluoro-richterite (FKM-65):
fluoro-richterite amphibole in metamorposed agpaitic syenite, with alkali feldspar
Cr-bearing katophorite/Cr-bearing glaucophane (FKM-394):
Cr-bearing (up to 0.32 Cr apfu) katophorite intergrown with Cr-bearing (up to 0.28 Cr apfu) glaucophane in sodic-amphibole jadeitite, with kosmochlor clinopyroxene
video pending video pending video pending video pending
ferro-ferri-katophorite
(FKM-249): ferro-ferri-katophorite to near boundary composition ferro-ferri-taramite amphibole in miaskitic nepheline syenite, with aegirine-augite clinopyroxene, alkali feldspar and nepheline
ferro-ferri-fluoro-katophorite
(FKM-305): ferro-ferri-fluoro-katophorite (0.94 F apfu; ~3.52 CFeT apfu) amphibole in alkali feldspar microsyenite, with Na-sanidine (K-feldspar)
hjalmarite (FKM-299):
Mn+Fe-bearing (0.67 B[Mn2++Ca] apfu with 0.47 BMn2+ apfu; 0.78 CMn2+ apfu; 0.65 CFe2+ apfu; preceding values based on ∑Si=8) hjalmarite amphibole in meta-Mn-metasomatite, with quartz, rhodonite and yoshimuraite
glaucophane (FKM-3):
glaucophane amphibole in blueschist, with jadeite clinopyroxene
glaucophane (FKM-100):
glaucophane amphibole in blueschist, with epidote, phengite mica and quartz
glaucophane (FKM-194):
glaucophane amphibole in siliceous blueschist, with quartz
riebeckite (FKM-139):
riebeckite amphibole in peralkaline granite pegmatite, with quartz, microcline and white mica
Cr-rich eckermannite (FKM-84):
variably Cr-enriched eckermannite amphibole in blueschist facies metamorphosed albitite, with Cr-jadeite and kosmochlor clinopyroxene and chlorite
Cr-rich eckermannite (FKM-381):
eckermannite amphibole (up to 0.XX Cr apfu) in blueschist facies metamorphosed albitite, with Cr-jadeite and kosmochlor clinopyroxene
[“chromio-eckermannite”]-[glaucophane] join (NaNa)-amphibole (FKM-394):
Cr-bearing (up to 0.92 Cr apfu) (NaNa)-amphibole along the “chromio-eckermannite”-glaucophane join in sodic-amphibole jadeitite, with kosmochlor clinopyroxene and albite plagioclase
video pending video pending video pending video pending
potassic-arfvedsonite
(FKM-320): potassic-arfvedsonite amphibole in nepheline syenite
magnesio-fluoro-arfvedsonite
(FKM-145): zoned magnesio-fluoro-arfvedsonite to fluoro-leakeite amphibole in agpaitic nepheline syenite, with aegirine clinopyroxene and fine-grained unidentified groundmass
potassic-magnesio-arfvedsonite
(FKM-39): zoned potassic-magnesio-arfvedsonite (core) to potassic-richterite (rim) amphibole in fenite-like K-metasomatite, with charoite and K-feldspar
holmquistite (FKM-164):
holmquistite amphibole in granite-adjacent Li-metasomatized wallrock, with quartz, chlorite and tourmaline
holmquistite (FKM-380):
holmquistite amphibole in granite-adjacent Li-metasomatized black-wall, with quartz, and biotite
fluoro-leakeite (FKM-175):
presumed fluoro-leakeite (Li analysis pending) in agpaitic nepheline syenite, with aegirine clinopyroxene, nepheline and alkali feldspar
“ferro-ferri-leakeite”/ferri-fluoro-leakeite
(FKM-431): “ferro-ferri-leakeite” (0.63 Fe2+ apfu; 0.56 Mn2+ apfu; 0.47 Mg apfu; 0.23 Zn apfu) with patchy ferri-fluoro-leakeite (0.78 Mg apfu; 0.45 Mn2+ apfu; 0.40 Fe2+ apfu; 0.26 Zn apfu; 1.05 F apfu) composite amphibole in Cs-B-Li-enriched granite, with aegirine-augite and quartz. Two optic axis figures (not differentiated) show the compositional variability
ferri-fluoro-leakeite (FKM-256):
ferri-fluoro-leakeite in albitized granite, with aegirine-augite, quartz and alkali feldspar (100X)
“mangano-ferri-fluoro-leakeite”
(FKM-430): “mangano-ferri-fluoro-leakeite” (0.60 Mn2+ apfu; 0.50 Mg apfu; 0.34 Zn apfu; 0.32 Fe2+ apfu; 0.84 F apfu; 0.77 [OH] apfu) amphibole in Cs-B-Li-enriched granite, with aegirine (200X)
the only observed crystal in the sample was not appropriately oriented to give a good figure
mangano-mangani-ungarettiite
(FKM-30): zoned mangano-mangani-ungarettiite to potassic-mangano-mangani-ungarettiite amphibole in meta-Mn-metasomatite, with serandite and quartz
inesite (FKM-76):
inesite in hydrothermal Mn-rich quartz-carbonate vein, with quartz and calcite
tinaksite (FKM-39b):
tinaksite in fenite-like K-metasomatite, with charoite
astrophyllite (FKM-227):
astrophyllite in nepheline syenite, with plagioclase and aegirine clinopyroxene
kupletskite-(Cs) (FKM-430):
kupletskite-(Cs) (by stoichiometry: 1.1 to 1.6 Cs apfu; astrophyllite group) in Cs-B-Li-enriched granite, with leucosphenite
aenigmatite (FKM-407):
aenigmatite in agpaitic nepheline syenite, with aegirine clinopyroxene, delhayelite, potassic-arfvedsonite amphibole, barytolamprophyllite and nepheline
crystals were too dark to obtain an optic figure
serendibite (FKM-135):
serendibite in calc-silicate high grade B-bearing Mg-calc-silicate, with tourmaline, phlogopite mica and calcite
serendibite (FKM-295):
serendibite in high grade B-bearing skarn, with diopside clinopyroxene
serendibite (FKM-371):
serendibite in high grade B-bearing skarn, with diopside clinopyroxene and spinel
sapphirine (FKM-11):
sapphirine (0.43 FeT apfu) in granulite facies meta-blackwall, with phlogopite mica
sapphirine (FKM-23):
sapphirine (up to 2.26 FeT apfu) in granulite facies metapelite, with cordierite, sillimanite, garnet and rutile
sapphirine (FKM-424):
sapphirine in granulite facies “sakenite”, with partially altered (pinitized) cordierite
neptunite (FKM-244):
neptunite in serpentine-hosted natrolite veins, with benitoite and natrolite(?)
leucosphenite (FKM-430):
leucosphenite in Cs-B-Li-enriched granite, with quartz and alkali feldspar

non-silicates in thin section

nesosilicates in thin section

sorosilicates and cyclosilicates in thin section

single chain inosilicates in thin section

phyllosilicates in thin section

tectosilicates and miscellaneous silicates in thin section