Unique Identification: Albite Site name: Bear Light type: Cross-Polarized Light Magnification: 400x Submitted by: Joe Smoot Notes: low birefringence of elongate prisms in multiple domains Image Tags: none | |
Unique Identification: Albite Site name: Bear Light type: Plane-Polarized Light Magnification: 400x Submitted by: Joe Smoot Notes: translucent, irregular outline with multiple prism shape domains internal Image Tags: test | |
Unique Identification: Amphibole Site name: Joseph Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Amphibole Site name: Petit du Fresnoy Light type: Plane-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Amphibole Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Guy Rothwell Notes: AE 326 100 + 150, amphibole broken crystals cleavage fragments pleochroic Image Tags: none | |
Unique Identification: Amphibole Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: Blue-to-green amphibole, rounded and worn Image Tags: blue-green | |
Unique Identification: Amphibole Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Rounded hornblende prism and crystal fragment, pleochroic in greens, prismatic crystal-fragment Image Tags: none | |
Unique Identification: Amphibole Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: Classic amphibole with green-to-brown pleochroism, moderate birefringence, low extinction angle Image Tags: greenish-brown good-cleavage | |
Unique Identification: Amphibole Site name: Fish Lake, Kenai Peninsula, Alaska Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Magmatic amphibole phenocryst with a quenched volcanic glass rind. Isotropic glass is extinct in cross-polarized light but visible as optical distortion on the birefringent surface of the grain. Image Tags: prismatic ferromagnesian amphibole colored mafic-mineral moderate-birefringence quenched-rind volcanic-glass | |
Unique Identification: Amphibole Site name: Southeast flank of Nicaragua Rise, Caribbean Sea (15 52.72 N, 74 36.47 W) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Rounded hornblende prism, pleochroic in greens, prismatic crystal-fragment Image Tags: none | |
Unique Identification: Amphibole Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 3000.0 Submitted by: Mark Shapley Notes: Prismatic amphibole; detrital Image Tags: prismatic good-cleavage hexagonal hornblende SEM | |
Unique Identification: Amphibole Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Guy Rothwell Notes: AE 326 100 + 150, amphibole broken crystals cleavage fragments pleochroic Image Tags: none | |
Unique Identification: Amphibole Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Guy Rothwell Notes: pleochroic in greens, amphibole broken crystals cleavage fragments pleochroic Image Tags: none | |
Unique Identification: Amphibole Site name: Yellowstone Light type: Cross-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: Classic amphibole with green-to-brown pleochroism, moderate birefringence, low extinction angle Image Tags: moderately-birefringent cleavage | |
Unique Identification: Amphibole Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Guy Rothwell Notes: AE 326 100 + 150, amphibole broken crystals cleavage fragments pleochroic Image Tags: none | |
Unique Identification: Amphibole Site name: Joseph Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Amphibole Site name: Fish Lake, Kenai Peninsula, Alaska Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Magmatic amphibole phenocryst with a quenched volcanic glass rind. Isotropic glass visible as an irregular transparent fringe along grain boundaries. Image Tags: prismatic ferromagnesian amphibole colored mafic-mineral moderate-birefringence quenched-rind volcanic-glass | |
Unique Identification: Amphibole Site name: Petit du Fresnoy Light type: Cross-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Apatite Site name: Jones Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: occurrence in Mazama tephra, euhedral volcanic Image Tags: none | |
Unique Identification: Apatite Site name: Lake Malawi Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: apatite, euhedral, diagenesis, from light colored lamina of varve Image Tags: none | |
Unique Identification: Apatite Site name: Lake Malawi Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: apatite, euhedral, diagenesis, from light colored lamina of varve Image Tags: none | |
Unique Identification: Apatite Site name: Jones Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: occurrence in Mazama tephra, euhedral volcanic Image Tags: none | |
Unique Identification: Aragonite Site name: Black Sea (43 00.29 N, 36 00.68 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: High power view of tritiform aragonite grains, resembling grains of rice or wheat, tritiform Image Tags: none | |
Unique Identification: Aragonite Site name: Pyramid Light type: Plane-Polarized Light Magnification: 400X Submitted by: Joe Smoot Notes: high relief, needles, broken diatoms Image Tags: none | |
Unique Identification: Aragonite Site name: Black Sea (43 00.29 N, 36 00.68 E) Light type: Cross-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: tritiform Image Tags: none | |
Unique Identification: Aragonite Site name: Black Sea (43 00.29 N, 36 00.68 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: High power view of tritiform aragonite grains, resembling grains of rice or wheat, tritiform Image Tags: none | |
Unique Identification: Aragonite Site name: Black Sea (42 05.94 N, 29 36.82 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of aragonite needles, acicular needles Image Tags: none | |
Unique Identification: Aragonite Site name: LacCore reference collection Light type: Plane-Polarized Light Magnification: 400X Submitted by: Val Stanley Notes: acicular habit Image Tags: none | |
Unique Identification: Backer rod Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: contaminant | |
Unique Identification: Backer rod Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: contaminant | |
Unique Identification: Backer rod Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: contaminant | |
Unique Identification: Backer rod Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: contaminant | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Banded carbonate mud Site name: Jones Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Barite Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Barite from a ferric tropical peatland. Ba-S compositions determined by EDX on numerous individual grains. Prismatic grains show low birefringence and moderate relief, variable terminations, and and were initially mistaken for apatite. Image Tags: low-birefringence moderate-relief diagenetic prismatic | |
Unique Identification: Barite Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Barite from a ferric tropical peatland. Ba-S compositions determined by EDX on numerous individual grains. Prismatic grains show low birefringence and moderate relief, variable terminations, and and were initially mistaken for apatite. Image Tags: low-birefringence moderate-relief diagenetic prismatic | |
Unique Identification: Barite Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Barite from a ferric tropical peatland. Ba-S compositions determined by EDX on numerous individual grains. Prismatic grains show low birefringence and moderate relief, variable terminations, and and were initially mistaken for apatite. Image Tags: low-birefringence moderate-relief diagenetic prismatic | |
Unique Identification: Barite Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Barite from a ferric tropical peatland. Ba-S compositions determined by EDX on numerous individual grains. Prismatic grains show low birefringence and moderate relief, variable terminations, and and were initially mistaken for apatite. Image Tags: low-birefringence moderate-relief diagenetic prismatic | |
Unique Identification: Barite Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Barite from a ferric tropical peatland. Ba-S compositions determined by EDX on numerous individual grains. Prismatic grains show low birefringence and moderate relief, variable terminations, and and were initially mistaken for apatite. Image Tags: low-birefringence moderate-relief diagenetic prismatic | |
Unique Identification: Barite Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Barite from a ferric tropical peatland. Ba-S compositions determined by EDX on numerous individual grains. Prismatic grains show low birefringence and moderate relief, variable terminations, and and were initially mistaken for apatite. Image Tags: low-birefringence moderate-relief diagenetic prismatic | |
Unique Identification: Biotite Site name: Lake Malawi Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: biotite, volcanic Image Tags: none | |
Unique Identification: Biotite Site name: Lake Malawi Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: biotite, volcanic Image Tags: none | |
Unique Identification: Biotite Site name: not specified Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: colored green platey heavy-mineral basal-section Image Tags: none | |
Unique Identification: Biotite Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: A thin book of biotite sheets, with torn edges Image Tags: flaky brown | |
Unique Identification: Biotite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Brown biotite mica flake, flakes Image Tags: none | |
Unique Identification: Biotite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Large green biotite mica flake, flakes Image Tags: none | |
Unique Identification: Biotite Site name: Big Soda Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: calcite-inclusion, Image Tags: none | |
Unique Identification: Biotite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Large biotite mica flake, note the conspicuously large size of the flake compared with the associated material, flakes Image Tags: none | |
Unique Identification: Biotite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of brown and green mica flakes, pyroxene crystal fragments also in the field, pyroxenes crystal-fragment flakes Image Tags: none | |
Unique Identification: Biotite Site name: not specified Light type: Cross-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: colored green platey heavy-mineral basal-section Image Tags: none | |
Unique Identification: Biotite Site name: Bengal Fan, Indian Ocean ( 8 00.42 N, 86 16.97 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of green and brown mica flakes, flakes Image Tags: none | |
Unique Identification: Biotite Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 7000.0 Submitted by: Mark Shapley Notes: Biotite; composition by EDX. Note platey phyllosilicate structure; in a smear slide, biotite grains will typically be viewed perpendicular to the cleavage plane, making this structure difficult to see. Image Tags: mica platey sheet good-cleavage SEM | |
Unique Identification: Biotite Site name: Reid Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Pleochroic halo from zircon in biotite; discoloration resulting from alpha particle irradiation Image Tags: none | |
Unique Identification: Biotite Site name: not specified Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: none Image Tags: none | |
Unique Identification: Biotite Site name: Big Soda Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: calcite-inclusion, Image Tags: none | |
Unique Identification: Biotite Site name: Ozera Karakul Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: vivid interference colors Image Tags: none | |
Unique Identification: Bubble Site name: not specified Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Bubble Site name: not specified Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Bubble Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Bubble Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Calcareous silt Site name: Lake McCarrons Light type: Plane-Polarized Light Magnification: not specified Submitted by: Amy Myrbo Notes: with pyrite Image Tags: pyrite | |
Unique Identification: Calcareous silt Site name: Lake McCarrons Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: with pyrite Image Tags: none | |
Unique Identification: Calcite Site name: Tanners Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: coarse polycrystalline twinned shallow-water Image Tags: none | |
Unique Identification: Calcite Site name: Tahltan Lake, BC, Canada Light type: Plane-Polarized Light Magnification: 400X Submitted by: Mark Shapley Notes: Triassic marine limestone Image Tags: corroded resorbed detrital pitted | |
Unique Identification: Calcite Site name: Tahltan Lake, BC, Canada Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Triassic marine limestone Image Tags: subangular anhedral detrital extreme-birefringence | |
Unique Identification: Calcite Site name: Itzan, Guatemala Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: limestone, calcite, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Calcite Site name: Titicaca Light type: Cross-Polarized Light Magnification: 630 Submitted by: Blas Valero Notes: transparent high-birefringent rhombohedric endogenic Image Tags: none | |
Unique Identification: Calcite Site name: Tahltan Lake, BC, Canada Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Triassic marine limestone Image Tags: corroded resorbed detrital pitted | |
Unique Identification: Calcite Site name: Titicaca Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent high-birefringent rhombohedric endogenic Image Tags: none | |
Unique Identification: Calcite Site name: Titicaca Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent high-birefringent rhombohedric endogenic Image Tags: none | |
Unique Identification: Calcite Site name: South Fraserdale, ON Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: limestone, calcite, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Calcite Site name: Miscanti Light type: Plane-Polarized Light Magnification: 100 Submitted by: Blas Valero Notes: highly birefringent, high relief elongated, coating fragments (Chara?) Image Tags: none | |
Unique Identification: Calcite Site name: Itzan, Guatemala Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: limestone, calcite, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Calcite Site name: Twin Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: polycrystalline Image Tags: none | |
Unique Identification: Calcite Site name: Negro Francisco Light type: Plane-Polarized Light Magnification: 630 Submitted by: Blas Valero Notes: transparent high-birefringent rhombohedric endogenic, could be dolomite Image Tags: none | |
Unique Identification: Calcite Site name: South Fraserdale, ON Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: limestone, calcite, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Calcite Site name: Miscanti Light type: Cross-Polarized Light Magnification: 100 Submitted by: Blas Valero Notes: highly birefringent, high relief elongated, coating fragments (Chara?) Image Tags: none | |
Unique Identification: Calcite Site name: not specified Light type: Cross-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: transparent high-birefringent rhombohedric detrital Image Tags: none | |
Unique Identification: Calcite Site name: Tahltan Lake, BC, Canada Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Triassic marine limestone Image Tags: subangular anhedral detrital extreme-birefringence | |
Unique Identification: Calcite Site name: Bear Light type: Cross-Polarized Light Magnification: 400 Submitted by: Joe Smoot Notes: multiple extinction domains with jagged boundaries, high birefringence Image Tags: none | |
Unique Identification: Calcite Site name: Titicaca Light type: Plane-Polarized Light Magnification: 630 Submitted by: Blas Valero Notes: transparent high-birefringent rhombohedric endogenic Image Tags: none | |
Unique Identification: Calcite Site name: Owens Light type: Plane-Polarized Light Magnification: 400X Submitted by: Joe Smoot Notes: dense translucent with bright internal grains, elongate with even width Image Tags: none | |
Unique Identification: Calcite Site name: Twin Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: rhombic equant Image Tags: none | |
Unique Identification: Calcite Site name: Tanners Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: coarse polycrystalline twinned shallow-water Image Tags: none | |
Unique Identification: Calcite Site name: Negro Francisco Light type: Cross-Polarized Light Magnification: 630 Submitted by: Blas Valero Notes: transparent high-birefringent rhombohedric endogenic, could be dolomite Image Tags: none | |
Unique Identification: Calcite Site name: Twin Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: polycrystalline Image Tags: none | |
Unique Identification: Calcite Site name: not specified Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: transparent high-birefringent rhombohedric detrital Image Tags: none | |
Unique Identification: Calcite Site name: Big Soda Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: calcite aggregates, transparent high-birefringent Image Tags: none | |
Unique Identification: Calcite Site name: Big Soda Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: calcite aggregates, transparent high-birefringent Image Tags: none | |
Unique Identification: Calcite Site name: Twin Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: rhombic equant Image Tags: none | |
Unique Identification: Chlorite Site name: Reid Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: Note anomalous interference colors. Image Tags: none | |
Unique Identification: Chlorite Site name: Bufflehead Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Note anomalous interference colors. Note pleochroic halo. Image Tags: none | |
Unique Identification: Chlorite Site name: Bufflehead Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: green | |
Unique Identification: Chlorite Site name: Reid Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: none Image Tags: flaky green | |
Unique Identification: Cigarette Ash Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Cigarette Ash Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Cigarette Ash Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Cigarette Ash Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay Site name: Superior Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay Site name: klin-2 Light type: Cross-Polarized Light Magnification: not specified Submitted by: Joe Smoot Notes: clay-rich mud with scattered silt grains and diatoms Image Tags: none | |
Unique Identification: Clay Site name: Superior Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay Site name: klin-2 Light type: Plane-Polarized Light Magnification: not specified Submitted by: Joe Smoot Notes: clay-rich mud with scattered silt grains and diatoms (synedra?) Image Tags: none | |
Unique Identification: Clay Site name: Superior Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay Site name: Superior Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay Site name: klin-2 Light type: Plane-Polarized Light Magnification: not specified Submitted by: Joe Smoot Notes: clay-rich mud with scattered silt grains and diatoms Image Tags: none | |
Unique Identification: Clay turbidite cap Site name: Twin Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay turbidite cap Site name: Twin Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay turbidite cap Site name: Twin Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clay turbidite cap Site name: Twin Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Clinopyroxene Site name: Yellowstone Light type: Cross-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: none Image Tags: weakly-pleochroic cleavage silicate pyroxene | |
Unique Identification: Clinopyroxene Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: none Image Tags: medium-birefringent silicate pyroxene | |
Unique Identification: Diatom ooze Site name: Herd Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Diatom ooze Site name: Herd Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Diatom ooze Site name: Herd Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Diatom ooze Site name: Herd Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Diatom ooze Site name: Herd Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Diatom ooze Site name: Herd Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Diatomaceous carbonate mud Site name: Lake McCarrons Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: Diverse elongate diatom forms interspersed with rhombic to ellipsoidal, colorless calcite up to 20 microns in dimension. Image Tags: rhombic | |
Unique Identification: Diatomaceous carbonate mud Site name: Lake McCarrons Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: Highly birefringent, rhombic to ellipsoidal calcite up to 20 microns in dimension; isotropic diatom frustules are extinct in cross-polarized light. Image Tags: rhombic | |
Unique Identification: Dolomite Site name: Pyramid Light type: Cross-Polarized Light Magnification: 400X Submitted by: Joe Smoot Notes: high birefringence, rhombic Image Tags: none | |
Unique Identification: Dolomite Site name: Bosumtwi Light type: Cross-Polarized Light Magnification: 630X Submitted by: Michael Rosen Blas Valero Notes: corroded rhombic transparent high-birefringent Image Tags: none | |
Unique Identification: Dolomite Site name: Red Lake Peatland Light type: Scanning Electron Micrograph Magnification: 5000.0 Submitted by: Mark Shapley Notes: Detrital dolomite (composition confirmed by EDX) from beneath a peatland. The denticulate texture is interpreted as the result of partial dissolution in a low-pH depositional environment. Through the petrographic microscope, partially dissolved carbonate mineral grains may exhibit prominent 'zig-zag' patterning to birefringence, due to etching along cleavage planes and grain boundaries. Image Tags: detrital toothed dissolution etched ragged reaction-texture SEM resorbed | |
Unique Identification: Dolomite Site name: Bosumtwi Light type: Plane-Polarized Light Magnification: 630X Submitted by: Michael Rosen Blas Valero Notes: corroded rhombic transparent high-birefringent Image Tags: none | |
Unique Identification: Dolomite Site name: Lake Bosumtwi Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Dolomite Site name: Red Lake Peatland Light type: Scanning Electron Micrograph Magnification: 1800.0 Submitted by: Mark Shapley Notes: Detrital dolomite (composition confirmed by EDX) from beneath a peatland. The denticulate texture is interpreted as the result of partial dissolution in a low-pH depositional environment. Through the petrographic microscope, partially dissolved carbonate mineral grains may exhibit prominent 'zig-zag' patterning to birefringence, due to etching along cleavage planes and grain boundaries. Image Tags: detrital toothed dissolution etched ragged reaction-texture SEM resorbed | |
Unique Identification: Dolomite Site name: Lake Bosumtwi Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Dolomite Site name: Red Lake Peatland Light type: Scanning Electron Micrograph Magnification: 1500.0 Submitted by: Mark Shapley Notes: Detrital dolomite (composition confirmed by EDX) from beneath a peatland. The denticulate texture is interpreted as the result of partial dissolution in a low-pH depositional environment. Through the petrographic microscope, partially dissolved carbonate mineral grains may exhibit prominent 'zig-zag' patterning to birefringence, due to etching along cleavage planes and grain boundaries. Image Tags: detrital toothed dissolution etched ragged reaction-texture SEM resorbed | |
Unique Identification: Dolomite Site name: Pyramid Light type: Plane-Polarized Light Magnification: 400X Submitted by: Joe Smoot Notes: high relief, rhombic Image Tags: none | |
Unique Identification: Dolomite Site name: Red Lake Peatland Light type: Scanning Electron Micrograph Magnification: 1200.0 Submitted by: Mark Shapley Notes: Detrital dolomite (composition confirmed by EDX) from beneath a peatland. The denticulate texture is interpreted as the result of partial dissolution in a low-pH depositional environment. Through the petrographic microscope, partially dissolved carbonate mineral grains may exhibit prominent 'zig-zag' patterning to birefringence, due to etching along cleavage planes and grain boundaries. Image Tags: detrital toothed dissolution etched ragged reaction-texture SEM resorbed | |
Unique Identification: Dolomite Site name: Bosumtwi Light type: Cross-Polarized Light Magnification: 630X Submitted by: Michael Rosen Blas Valero Notes: euhedral, rhombic transparent high-birefringent Image Tags: none | |
Unique Identification: Dolomite Site name: Red Lake Peatland Light type: Scanning Electron Micrograph Magnification: 1200.0 Submitted by: Mark Shapley Notes: Detrital dolomite (composition confirmed by EDX) from beneath a peatland. The denticulate texture is interpreted as the result of partial dissolution in a low-pH depositional environment. Through the petrographic microscope, partially dissolved carbonate mineral grains may exhibit prominent 'zig-zag' patterning to birefringence, due to etching along cleavage planes and grain boundaries. Image Tags: detrital toothed dissolution etched ragged reaction-texture SEM resorbed | |
Unique Identification: Dolomite Site name: Bosumtwi Light type: Plane-Polarized Light Magnification: 630X Submitted by: Michael Rosen Blas Valero Notes: rhombic transparent high-birefringent Image Tags: none | |
Unique Identification: Dolomite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Euhedral dolomite rhomb, rhombic Image Tags: none | |
Unique Identification: Erionite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 2500.0 Submitted by: Mark Shapley Notes: Radiating fibrous habit of erionite from altered mafic volcaniclastic rocks; apparent under petrographic scope only at high magnification. This zeolite-family mineral is recognized as an inhalation hazard. Image Tags: SEM zeolite fibrous needle low_relief low_birefringence diagenetic radial volcanic_glass health_hazard alteration | |
Unique Identification: Erionite Site name: Paleolake Idaho, ID Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Erionite cement nadhering to a quartz grain. Image Tags: fibrous diagenetic acicular radial alteration zeolite | |
Unique Identification: Erionite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 7000.0 Submitted by: Mark Shapley Notes: Radiating fibrous habit of erionite from altered mafic volcaniclastic rocks; apparent under petrographic scope only at high magnification. This zeolite-family mineral is recognized as an inhalation hazard. Note brittle fracture of individual fibers. Image Tags: SEM zeolite fibrous needle low_relief low_birefringence diagenetic radial volcanic_glass health_hazard alteration | |
Unique Identification: Erionite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 1500.0 Submitted by: Mark Shapley Notes: Radiating fibrous habit of erionite from altered mafic volcaniclastic rocks; apparent under petrographic scope only at high magnification. This zeolite-family mineral is recognized as an inhalation hazard. Image Tags: SEM zeolite fibrous needle low_relief low_birefringence diagenetic radial volcanic_glass health_hazard alteration | |
Unique Identification: Erionite Site name: Paleolake Idaho, ID Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: The zeolite erionite forming a cement on feldspar silt grain. Image Tags: fibrous diagenetic acicular radial alteration zeolite | |
Unique Identification: Erionite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 1500.0 Submitted by: Mark Shapley Notes: Radiating fibrous habit of erionite from altered mafic volcaniclastic rocks; apparent under petrographic scope only at high magnification. This zeolite-family mineral is recognized as an inhalation hazard. Image Tags: SEM zeolite fibrous needle low_relief low_birefringence diagenetic radial volcanic_glass health_hazard alteration | |
Unique Identification: Erionite Site name: Paleolake Idaho, ID Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Cement-forming erionite in cross-polarized light, encrusting a feldspar grain. Highly birefringent acicular bundles in upper right are an unidentified accessory mineral. Image Tags: fibrous diagenetic acicular radial alteration zeolite | |
Unique Identification: Erionite Site name: Paleolake Idaho, ID Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Erionite cement nadhering to a quartz grain. Image Tags: fibrous diagenetic acicular radial alteration zeolite | |
Unique Identification: Erionite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 6000.0 Submitted by: Mark Shapley Notes: Radiating fibrous habit of erionite from altered mafic volcaniclastic rocks; apparent under petrographic scope only at high magnification. This zeolite-family mineral is recognized as an inhalation hazard. Note brittle fracture of individual fibers. Image Tags: SEM zeolite fibrous needle low_relief low_birefringence diagenetic radial volcanic_glass health_hazard alteration | |
Unique Identification: Erionite Site name: Paleolake Idaho, ID Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Very fine fibrous bundles of erionite, formed diagenetically in a weathering volcaniclastic sandstone derived from basalts of the Snake Rive Plain, Idaho. Erionite in this form represents a potential inhalation hazard. Image Tags: fibrous diagenetic acicular radial alteration | |
Unique Identification: Erionite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 2000.0 Submitted by: Mark Shapley Notes: Radiating fibrous habit of erionite from altered mafic volcaniclastic rocks; apparent under petrographic scope only at high magnification. This zeolite-family mineral is recognized as an inhalation hazard. Image Tags: SEM zeolite fibrous needle low_relief low_birefringence diagenetic radial volcanic_glass health_hazard alteration | |
Unique Identification: Fecal pellet Site name: Pyramid Light type: Plane-Polarized Light Magnification: 400 Submitted by: Joe Smoot Notes: clay with aragonite needles, dark clots are brine shrimp fecal pellets Image Tags: none | |
Unique Identification: Fecal pellet Site name: Great Salt Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Cohen Notes: brine shrimp fecal pellet Image Tags: none | |
Unique Identification: Fecal pellet Site name: Great Salt Lake Light type: Reflected Light Magnification: not specified Submitted by: Andy Cohen Notes: brine shrimp fecal pellet Image Tags: none | |
Unique Identification: Feldspar Site name: Bear Light type: Plane-Polarized Light Magnification: 400 Submitted by: Joe Smoot Notes: Feldspar grain near image center. Low birefringence, twinning lamellae Image Tags: none | |
Unique Identification: Feldspar Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Large magmatic feldspar showing prominent orthogonal cleavage. Image Tags: tabular good-cleavage feldspar | |
Unique Identification: Feldspar Site name: Reid Lake, ON Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: microcline, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Feldspar Site name: Fish Lake, Kenai Peninsula, Alaska Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Large mineral inclusions and quenched glassy rind (scaly surface texture) distinguish twinned feldspar phenocrysts derived from an unidentified crystal-rich tephra. Image Tags: twinned inclusions quenched-rind tephra | |
Unique Identification: Feldspar Site name: Fish Lake, Kenai Peninsula, Alaska Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Large mineral inclusions and quenched glassy rind (scaly surface texture) distinguish twinned feldspar phenocrysts derived from an unidentified crystal-rich tephra. Image Tags: twinned inclusions quenched-rind tephra | |
Unique Identification: Feldspar Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 1500.0 Submitted by: Mark Shapley Notes: Angular detrital feldspar grain with prominent cleavage from a volcaniclastic sandstone. Image Tags: SEM cleavage tabular | |
Unique Identification: Feldspar Site name: Reid Lake, ON Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: microcline, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Feldspar Site name: Paleolake Idaho, ID Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Very well-rounded silt-sized feldspar grain; aeolian? Image Tags: cleavage rounded low-birefringence | |
Unique Identification: Feldspar Site name: Bear Light type: Cross-Polarized Light Magnification: 400 Submitted by: Joe Smoot Notes: Feldspar grain near image center; matrix of high relief aragonite needles of consistent size Image Tags: none | |
Unique Identification: Feldspar Site name: Reid Lake, ON Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: microcline, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Feldspar Site name: Paleolake Idaho, ID Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Very well-rounded silt-sized feldspar grain; aeolian? Image Tags: cleavage rounded low-birefringence | |
Unique Identification: Feldspar Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 7000.0 Submitted by: Mark Shapley Notes: Textural detail of the cleavage structure in an angular detrital feldspar grain from a volcaniclastic sandstone. Image Tags: SEM cleavage tabular | |
Unique Identification: Feldspar Site name: Fish Lake, Kenai Peninsula, Alaska Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Large mineral inclusions and quenched glassy rind (scaly surface texture) distinguish twinned feldspar phenocrysts derived from an unidentified crystal-rich tephra. Image Tags: twinned inclusions quenched-rind tephra | |
Unique Identification: Feldspar Site name: Reid Lake, ON Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: microcline, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Feldspar Site name: Fish Lake, Kenai Peninsula, Alaska Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Large mineral inclusions and quenched glassy rind (scaly surface texture) distinguish twinned feldspar phenocrysts derived from an unidentified crystal-rich tephra. Image Tags: twinned inclusions quenched-rind tephra | |
Unique Identification: Feldspar Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Large magmatic feldspar showing prominent orthogonal cleavage. Birefringence exceeds that normally described for feldspars due to the large size of the grain. Image Tags: tabular good-cleavage feldspar | |
Unique Identification: Feldspar Site name: Tyrrhenian Sea, Mediterranean Sea Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Euhedral feldspar crystal showing oscillatory zoning, crystal surrounded by a thin envelope of glass, showing pyroclastic origin. Volcanic glass also in the field., oscillatory-twinning pyroclastic volcanic-glass Image Tags: none | |
Unique Identification: Fiber Site name: Berendon Pond Light type: not specified Magnification: 400x Submitted by: Ian Walker Notes: none Image Tags: fiberous string blue | |
Unique Identification: Fiber Site name: Reid Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Fiber Site name: Peten Itza Light type: not specified Magnification: 100.0 Submitted by: Jordon Bright Notes: none Image Tags: red thread-like | |
Unique Identification: Floral Foam Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Floral Foam Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Floral Foam Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Floral Foam Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Garnet Site name: Lake Van Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: hexagonal | |
Unique Identification: Garnet Site name: Reid Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: isotropic, note rounded hexagonal profile Image Tags: rounded | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glacial varves Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Glauconite Site name: Feni Drift, Rockall Trough, NE Atlantic (53 13.46 N, 18 53.69 W) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Glauconite grains - picked fraction, aggregate Image Tags: none | |
Unique Identification: Glauconite Site name: Lower continental rise, west of Cape Agulhas, South Africa (35 03.97 S, 15 26.91 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Irregular and smooth glauconite grains, aggregate Image Tags: none | |
Unique Identification: Glauconite Site name: Lower continental rise, west of Cape Agulhas, South Africa (35 03.97 S, 15 26.91 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Irregular and smooth glauconite grains, aggregate Image Tags: none | |
Unique Identification: Glauconite Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Guy Rothwell Notes: SIOCLMR 173 G, Image Tags: none | |
Unique Identification: Glauconite Site name: Owens Light type: Plane-Polarized Light Magnification: 400 Submitted by: Joe Smoot Notes: dark green nonpleochroic Image Tags: none | |
Unique Identification: Gypsum Site name: Hurleg Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: rutilated | |
Unique Identification: Gypsum Site name: Miscanti Light type: Plane-Polarized Light Magnification: 100 Submitted by: Blas Valero Notes: transparent low-birefringent monoclinic euhedral corroded Image Tags: none | |
Unique Identification: Gypsum Site name: Peten Itza Light type: Plane-Polarized Light Magnification: 100 Submitted by: Michael Rosen Blas Valero Notes: transparent low-birefringent monoclinic euhedral Image Tags: none | |
Unique Identification: Gypsum Site name: Atacama Light type: Cross-Polarized Light Magnification: 100 Submitted by: Michael Rosen Blas Valero Notes: transparent, carbonate inclusions, euhedral Image Tags: none | |
Unique Identification: Gypsum Site name: Hurleg Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Great Salt Lake, UT Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: gypsum, authigenic Image Tags: none | |
Unique Identification: Gypsum Site name: Hurleg Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Great Salt Lake, UT Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: gypsum, authigenic Image Tags: none | |
Unique Identification: Gypsum Site name: Peten Itza Light type: Cross-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: carbonate inclusions, transparent low-birefringent monoclinic euhedral Image Tags: none | |
Unique Identification: Gypsum Site name: Hurleg Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Peten Itza Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: carbonate inclusions, transparent low-birefringent monoclinic euhedral Image Tags: none | |
Unique Identification: Gypsum Site name: Miscanti Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Miscanti Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Hurleg Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Hurleg Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Gypsum Site name: Peten Itza Light type: Cross-Polarized Light Magnification: 100 Submitted by: Michael Rosen Blas Valero Notes: transparent low-birefringent monoclinic euhedral Image Tags: none | |
Unique Identification: Gypsum Site name: Atacama Light type: Plane-Polarized Light Magnification: 100 Submitted by: Michael Rosen Blas Valero Notes: transparent, carbonate inclusions, euhedral Image Tags: none | |
Unique Identification: Gypsum Site name: Miscanti Light type: Cross-Polarized Light Magnification: 100 Submitted by: Blas Valero Notes: transparent low-birefringent monoclinic euhedral corroded Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Hair Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Inclusion Site name: Petit du Fresnoy Light type: Cross-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: detrital Image Tags: lithic | |
Unique Identification: Inclusion Site name: Ozera Karakul Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Inclusion Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Fine acicular inclusions in a twinned tabular feldspar(?) Image Tags: inclusions acicular feldspar twinned | |
Unique Identification: Inclusion Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Fine acicular inclusions in a twinned tabular feldspar(?) Image Tags: inclusions acicular feldspar twinned | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Malawi Light type: Plane-Polarized Light Magnification: not specified Submitted by: AM Notes: none Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Urswick Tarn Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: Hematite red brown transparent translucent opaque isotropic oxide heavy-mineral | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Medicine Lake, MT Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Patchy hematite precipitation on a rounded feldspar sand grain. Strong reddish-brown color obscures birefringence. Fine carbonate grains also adhere to the grain surface. Image Tags: amorphous red colored oxide | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Lake Mackenzie Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: Hematite red brown transparent translucent opaque isotropic oxide heavy-mineral | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Tasmania Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: orange brown altered Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: R.K. Light type: Cross-Polarized Light Magnification: not specified Submitted by: Joe Smoot Notes: matrix shows low birefringence, needles have high birefringent margins Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: LacCore reference collection Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: iron oxides replacing rim of calcite grain Image Tags: pseudomorphing | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: LacCore reference collection Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: LacCore reference collection Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Tasmania Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: orange brown altered Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: R.K. Light type: Plane-Polarized Light Magnification: not specified Submitted by: Joe Smoot Notes: vermiform texture in matrix with many needle-like clear forms Image Tags: none | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Medicine Lake, MT Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Patchy hematite precipitation on a rounded feldspar sand grain. Fine carbonate grains also adhere to the grain surface. Image Tags: amorphous red colored oxide | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Lake Mackenzie Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: Hematite red brown transparent translucent opaque isotropic oxide heavy-mineral | |
Unique Identification: Iron (Hydr)oxides, Non-opaque (Hematite/Limonite) Site name: Urswick Tarn Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: Hematite red brown transparent translucent opaque isotropic oxide heavy-mineral | |
Unique Identification: Iron Oxides, Opaque (e.g., magnetite) Site name: Mountain Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Magnetite in a well-rounded sand layer from Mountain Lake (San Francisco, California). Image Tags: heavy-mineral rounded opaque-oxide magnetite | |
Unique Identification: Iron Oxides, Opaque (e.g., magnetite) Site name: Mountain Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Magnetite in a well-rounded sand layer from Mountain Lake (San Francisco, California). Image Tags: heavy-mineral rounded opaque-oxide magnetite | |
Unique Identification: Iron Oxides, Opaque (e.g., magnetite) Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: iron oxides replacing rim of calcite grain Image Tags: pseudomorphing | |
Unique Identification: Iron Oxides, Opaque (e.g., magnetite) Site name: Mountain Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Magnetite in a well-rounded sand layer from Mountain Lake (San Francisco, California). Image Tags: heavy-mineral rounded opaque-oxide magnetite | |
Unique Identification: Iron Oxides, Opaque (e.g., magnetite) Site name: Mountain Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Magnetite in a well-rounded sand layer from Mountain Lake (San Francisco, California). Image Tags: heavy-mineral rounded opaque-oxide magnetite | |
Unique Identification: Iron Oxides, Opaque (e.g., magnetite) Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: iron oxides replacing rim of calcite grain Image Tags: pseudomorphing | |
Unique Identification: Kimwipe Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Kimwipe Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Kimwipe Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Kimwipe Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Lab Dust Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Lab Dust Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Lab Dust Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Lab Dust Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Laminated sulfidic silt Site name: Wallowa Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Siliciclastic medium silt and diatom frustules with abundant, fine-grained opaque minerals. This sediment reacted dramatically within an hour or two of core splitting, as reactive Fe sulfides oxidized in contact with air. Image Tags: none | |
Unique Identification: Laminated sulfidic silt Site name: Wallowa Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Alteration of volcanic glass (irregular grains with conchoidal fracture, center and lower right, nearly isotropic in cross-polarized light below) provide another potential source of Fe for the formation of reactive iron sulfides. Image Tags: none | |
Unique Identification: Laminated sulfidic silt Site name: Wallowa Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Medium siliciclastic (quartz + feldspars) angular silt; isotropic diatoms and opaque iron sulfides are invisible in cross-polarized light. Image Tags: none | |
Unique Identification: Laminated sulfidic silt Site name: Wallowa Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: Iron-bearing silicate minerals derived from igneous rocks (flaky biotite upper left and lower right; prismatic pyroxenes top center and bottom near scale bar) are potential sources of reactive Fe contributing to iron sulfide formation in this sediment. Image Tags: none | |
Unique Identification: Laminated sulfidic silt Site name: Wallowa Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: Birefringent pyroxene grain in upper middle of image is in extinction orientation; pyroxene near scale bar shows moderate birefringence. Axial view of biotite flake (upper left) shows minimal birefringence. Image Tags: none | |
Unique Identification: Laminated sulfidic silt Site name: Wallowa Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Lithic fragment Site name: Petit du Fresnoy Light type: Cross-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: detrital; aggregate of other minerals Image Tags: lithic | |
Unique Identification: Lithic fragment Site name: Petit du Fresnoy Light type: Plane-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: detrital; aggregate of other minerals Image Tags: lithic | |
Unique Identification: Magadiite Site name: Kitagata Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: magadiite, hematite, identified by Jim Russell Image Tags: hematite | |
Unique Identification: Magadiite Site name: Kitagata Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: magadiite, hematite, identified by Jim Russell Image Tags: hematite | |
Unique Identification: Microcline Site name: Lake of the Woods Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Val Stanley Notes: Note diagnostic twinning pattern. Image Tags: cross-hatched-twinning tartanplaid | |
Unique Identification: Microcline Site name: Lake Eyasi Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Microcline Site name: Lake of the Woods Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Val Stanley Notes: 90 degree cleavages Image Tags: transparent | |
Unique Identification: Microcline Site name: Lake Eyasi Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Microcline Site name: Lake Eyasi Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Mold Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Mold Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Mold Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Mold Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Cross-Polarized Light Magnification: not specified Submitted by: AM Notes: none Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Cross-Polarized Light Magnification: not specified Submitted by: AM Notes: none Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent flaky low birefringent Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Plane-Polarized Light Magnification: not specified Submitted by: AM Notes: none Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent flaky low birefringent Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent flaky low birefringent Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent flaky low birefringent Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent flaky low birefringent Image Tags: none | |
Unique Identification: Muscovite Site name: Malawi Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent flaky low birefringent Image Tags: none | |
Unique Identification: Olivine Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Olivine phenocryst from a basaltic tephra originating in the Snake River Plain, Idaho. Moderate but vivid birefringence is characteristic. Image Tags: mafic-mineral high-relief high-birefringence conchoidal-fracture | |
Unique Identification: Olivine Site name: Lake of the Woods Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Val Stanley Notes: none Image Tags: conchoidal-fracture green | |
Unique Identification: Olivine Site name: Lake of the Woods Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Amy Myrbo Notes: Olivine Image Tags: none | |
Unique Identification: Olivine Site name: Lake of the Woods Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Amy Myrbo Notes: Olivine Image Tags: none | |
Unique Identification: Olivine Site name: Lake of the Woods Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Amy Myrbo Notes: Olivine Image Tags: none | |
Unique Identification: Olivine Site name: Ozera Karakul Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: conchoidal fracture, green, high relief Image Tags: conchoidal-fracture | |
Unique Identification: Olivine Site name: Lake of the Woods Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Val Stanley Notes: none Image Tags: conchoidal-fracture green | |
Unique Identification: Olivine Site name: Lake of the Woods Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Amy Myrbo Notes: Olivine Image Tags: none | |
Unique Identification: Olivine Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Olivine phenocryst from a basaltic tephra originating in the Snake River Plain, Idaho. Note high relief and conchoidal fracture. Minimum aeolian transport of 125 km is implied for this sand-sized, high-density grain. Image Tags: mafic-mineral high-relief high-birefringence conchoidal-fracture | |
Unique Identification: Olivine Site name: Ozera Karakul Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: green | |
Unique Identification: Opal Site name: Lake Malawi Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: opal, diagenesis Image Tags: none | |
Unique Identification: Organic-rich carbonate mud with pyrite Site name: Lake McCarrons Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Organic-rich carbonate mud with pyrite Site name: Lake McCarrons Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Organic-rich Diatom Ooze Site name: Waswaagining/Haskell Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Organic-rich Diatom Ooze Site name: Waswaagining/Haskell Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Organic-rich Diatom Ooze Site name: Waswaagining/Haskell Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Organic-rich Diatom Ooze Site name: Waswaagining/Haskell Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Orthopyroxene Site name: Round Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic silicate pyroxene | |
Unique Identification: Orthopyroxene Site name: Round Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic silicate pyroxene | |
Unique Identification: Orthopyroxene Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: vivid orange in color in this case Image Tags: orange pleochroic cleavage silicate pyroxene | |
Unique Identification: Orthopyroxene Site name: Round Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic silicate pyroxene | |
Unique Identification: Orthopyroxene Site name: Round Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic silicate pyroxene | |
Unique Identification: Orthopyroxene Site name: Yellowstone Light type: Cross-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: none Image Tags: cleavage moderately birefringent silicate pyroxene | |
Unique Identification: Palagonite Site name: Abyssal hill, Madeira Abyssal Plain, NE Atlantic Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of palagonitised volcanic glass, volcanic-glass Image Tags: none | |
Unique Identification: Palagonite Site name: Abyssal hill, Madeira Abyssal Plain, NE Atlantic Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of palagonitised volcanic glass, flow-banding visible in one grain (top right), volcanic-glass Image Tags: none | |
Unique Identification: Peat Site name: Middle Sugarbush Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Peat Site name: Middle Sugarbush Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Peat Site name: Middle Sugarbush Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Peat Site name: Middle Sugarbush Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Phillipsite Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Guy Rothwell Notes: complex rosette, zeolite rosette Image Tags: none | |
Unique Identification: Phillipsite Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Guy Rothwell Notes: cruciform twin, zeolite cruciform twin feldspar Image Tags: none | |
Unique Identification: Phillipsite Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Guy Rothwell Notes: broken cruciform twins and rosettes, zeolites prismatic rosettes cruciform twins Image Tags: none | |
Unique Identification: Phillipsite Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Guy Rothwell Notes: broken rosette, zeolites prismatic rosette Image Tags: none | |
Unique Identification: Phillipsite Site name: King's Trough, NE Atlantic (44 02.80 N, 21 47.03 W) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of phillipsite crystals, mostly single and broken prismatic crystals, but also partial rosettes and a partial cruciform twin in the field, zeolites cruciform prismatic Image Tags: none | |
Unique Identification: Phillipsite Site name: King's Trough, NE Atlantic (44 02.80 N, 21 47.03 W) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of phillipsite crystals, mostly single and broken prismatic crystals, but including partial rosette, zeolites rosette prismatic Image Tags: none | |
Unique Identification: Phillipsite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of phillipsite crystals, mostly single and broken prismatic crystals, but including broken cruciform twins and complexly intergrown crystals, zeolites rosette cruciform prismatic Image Tags: none | |
Unique Identification: Pirssonite Site name: Owens Light type: Cross-Polarized Light Magnification: 400 Submitted by: Joe Smoot Notes: high birefringence Image Tags: none | |
Unique Identification: Plagioclase Site name: Chungara Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent twinned medium relief low birefringent Image Tags: none | |
Unique Identification: Plagioclase Site name: Joseph Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: none | |
Unique Identification: Plagioclase Site name: Joseph Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: exsolution lamellae Image Tags: none | |
Unique Identification: Plagioclase Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: cracked high-relief | |
Unique Identification: Plagioclase Site name: Chungara Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent twinned low relief low birefringent Image Tags: none | |
Unique Identification: Plagioclase Site name: South of Java Trench, NE Indian Ocean (9 46.53 S, 102.41.95) Light type: Cross-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Subhedral plagioclase crystal showing polysynthetic twinning on the albite law, twinned Image Tags: none | |
Unique Identification: Plagioclase Site name: Chungara Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent twinned low relief low birefringent Image Tags: none | |
Unique Identification: Plagioclase Site name: Chungara Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent twinned medium relief low birefringent Image Tags: none | |
Unique Identification: Plagioclase Site name: Yellowstone Light type: Cross-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: Twinning lamellae, with undulose extinction Image Tags: twinned undulose-extinction | |
Unique Identification: Plagioclase Site name: Chungara Light type: Plane-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent twinned low relief low birefringent Image Tags: none | |
Unique Identification: Plagioclase Site name: Chungara Light type: Cross-Polarized Light Magnification: 400 Submitted by: Blas Valero Notes: transparent twinned low relief low birefringent Image Tags: none | |
Unique Identification: Plagioclase Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: Plagioclase with twins that persist in plane light Image Tags: twinned | |
Unique Identification: Plagioclase Site name: Reid Lake, ON Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: plagioclase, limestone, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Plagioclase Site name: Reid Lake, ON Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: plagioclase, limestone, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Plagioclase Site name: Yellowstone Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: cracked high-relief | |
Unique Identification: Polycarb Large Fragment Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Large Fragment Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Large Fragment Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Large Fragment Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Small Fragment Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Small Fragment Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Small Fragment Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Polycarb Small Fragment Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Pyrite Site name: Angola Basin, SE Atlantic (19 11.26 S, 9 23.17 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Cluster of framboidal pyrite enclosed within centric diatom frustule, isolated and clustered pyrite framboids and biogenic siliceous debris also in the field, framboid centric-diatoms siliceous-debris biogenic-silica Image Tags: none | |
Unique Identification: Pyrite Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 4000.0 Submitted by: Mark Shapley Notes: Two framboidal pyrite aggregates embedded in organic matter. Under the petrographic microscope, spheres are opaque and individual crystallites are generally not resolved. Image Tags: framboid opaque sperical crystallites polycrystalline SEM | |
Unique Identification: Pyrite Site name: not specified Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: filling-diatom Image Tags: none | |
Unique Identification: Pyrite Site name: Titicaca Light type: Plane-Polarized Light Magnification: 630 Submitted by: Blas Valero Notes: opaque isotropic euhedral cubic Image Tags: none | |
Unique Identification: Pyrite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Euhedral pyrite, forms include discrete octahedra and pyritohedra. Clumps of clay and colourless prismatic zeolite crystals also in the field, pyritohedra octahedra prismatic zeolite clay Image Tags: none | |
Unique Identification: Pyrite Site name: Western edge of the Sigsbee Deep, Gulf of Mexico (23 47.80 N, 94 46.09 W) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Euhedral pyrite, forms include discrete octahedra and pyritohedra. Clumps of clay and colourless prismatic zeolite crystals also in the field, pyritohedra octahedra prismatic zeolite clay Image Tags: none | |
Unique Identification: Pyrite Site name: Big Soda Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: isotropic euhedral opaque Image Tags: none | |
Unique Identification: Pyrite Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Guy Rothwell Notes: pyrityohedra zeolites Image Tags: none | |
Unique Identification: Pyrite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 10000.0 Submitted by: Mark Shapley Notes: Complexly tiled and twinned FeS2 framboid from an altered volcaniclastic sandstone; possibly marcasite. An opaque unitary sphere through the petrographic scope. Image Tags: opaque black spherical framboid SEM marcasite crystallites polycrystalline sulfide | |
Unique Identification: Pyrite Site name: Angola Basin, SE Atlantic (19 11.26 S, 9 23.17 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Dispersed framboidal pyrite, framboidal pyrite within foraminifera test, centric diatoms and diatom debris and clumps of clay in the field, framboid centric-diatoms siliceous-debris biogenic-silica clay Image Tags: none | |
Unique Identification: Pyrite Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 5000.0 Submitted by: Mark Shapley Notes: Two framboidal pyrite aggregates embedded in dispersed <1 micron pyrite crystallites. Under the petrographic microscope, disaggregated crystallites would appear as gray cloudy masses. Image Tags: framboid opaque sperical crystallites polycrystalline SEM | |
Unique Identification: Pyrite Site name: Green Pepper Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Pyrite Site name: Crater Lake Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: none Image Tags: none | |
Unique Identification: Pyrite Site name: Angola Basin, SE Atlantic (19 11.26 S, 9 23.17 E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Clusters of framboidal pyrite enclosed within centric diatom frustules, isolated and clustered pyrite framboids and biogenic siliceous debris also in the field, framboid centric-diatoms siliceous-debris biogenic-silica Image Tags: none | |
Unique Identification: Pyrite Site name: Paleolake Idaho Light type: Scanning Electron Micrograph Magnification: 3000.0 Submitted by: Mark Shapley Notes: Framboids and disseminated crystallites of FeS2 (pyrite, lower, and possible marcasite, center) in altered volcaniclastic sandstone. Through the petrographic microscope, framboids would appear as unitary opaque spheres, and crystallites as very fine opaque euhedra or gray cloudy masses. A small fibrous bundle of the zeolite mineral erionite is visible at center left. Image Tags: opaque black spherical framboid SEM crystallites polycrystalline sulfide marcasite | |
Unique Identification: Pyrite Site name: Malawi Light type: Plane-Polarized Light Magnification: not specified Submitted by: AM Notes: none Image Tags: diatom | |
Unique Identification: Pyroxene Site name: Lake of the Woods Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Val Stanley Notes: 90 degree cleavages Image Tags: green high-relief perpendicular-cleavage | |
Unique Identification: Pyroxene Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Large dark-colored magmatic pyroxene grain from a basaltic tephra originating in the Snake River Plain, Idaho. First-and-second-order birefringence is obscured by strong grain coloration. Image Tags: pyroxene mafic-mineral moderate-birefringence prismatic ferromagnesian | |
Unique Identification: Pyroxene Site name: Lake of the Woods Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Val Stanley Notes: 90 degree cleavages Image Tags: high-relief perpendicular-cleavage | |
Unique Identification: Pyroxene Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Large dark-colored magmatic pyroxene grain from a basaltic tephra originating in the Snake River Plain, Idaho. Fragmentary plant matter underlies the grain. Image Tags: pyroxene mafic-mineral moderate-birefringence prismatic ferromagnesian | |
Unique Identification: Quartz Site name: Reid Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: angular quartz, undulose extinction, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Quartz Site name: Arthurs Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Note inclusions in quartz, likely rutilated Image Tags: rutilated | |
Unique Identification: Quartz Site name: South Fraserdale, ON Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: angular quartz, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Quartz Site name: not specified Light type: Cross-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of poorly sorted angular quartz grains, anhedral Image Tags: none | |
Unique Identification: Quartz Site name: South Fraserdale, ON Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: angular quartz, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Quartz Site name: not specified Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: well-rounded; stain Image Tags: none | |
Unique Identification: Quartz Site name: not specified Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: Well-rounded; sand-sized grain gives higher-order birefringence colors that expected for typical quartz silt. Image Tags: none | |
Unique Identification: Quartz Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: Rutilated Image Tags: none | |
Unique Identification: Quartz Site name: Reid Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: Angular quartz, undulose extinction, detrital, glaciolacustrine Image Tags: none | |
Unique Identification: Quartz Site name: not specified Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: well-rounded; stain Image Tags: none | |
Unique Identification: Quartz Site name: not specified Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: rounded coarse-grained Image Tags: none | |
Unique Identification: Quartz Site name: St. Louis River Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Note inclusion trails within quartz grain Image Tags: none | |
Unique Identification: Rhodochrosite Site name: Lewis Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: pleochroic xrd-confirmation Image Tags: none | |
Unique Identification: Rhodochrosite Site name: Lewis Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: pleochroic xrd-confirmation Image Tags: none | |
Unique Identification: Rhodochrosite Site name: Lewis Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: pleochroic xrd-confirmation Image Tags: none | |
Unique Identification: Rhodochrosite Site name: Lewis Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: pleochroic xrd-confirmation Image Tags: none | |
Unique Identification: Rhodochrosite Site name: Lewis Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: pleochroic xrd-confirmation Image Tags: none | |
Unique Identification: Rhodochrosite Site name: Lewis Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: pleochroic xrd-confirmation Image Tags: none | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Two high-relief titanium-bearing mineral grains (6 o'clock and 12 o'clock) from basal material underlying a tropical peatland. Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 1500.0 Submitted by: Mark Shapley Notes: Diagenetic rutile aggregate; composition by EDX. Under petrographic scope, individual acicular prisms are tiny, have high relief, and very high birefringence for their size. Image Tags: diagenetic elongate acicular twinned SEM | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 4000.0 Submitted by: Mark Shapley Notes: Diagenetic rutile aggregate embedding unidentified dark mineral Image Tags: diagenetic twinned elongate SEM | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Unusually large titanium-bearing mineral grain from basal material underlying a tropical peatland. Grains from this interval analyzed by energy dispersive xray spectrometry (EDX) show simple compositions near that of rutile (TiO2). Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 8000.0 Submitted by: Mark Shapley Notes: Twinned diagenetic rutile, composition by EDX. Image Tags: arrowhead twinned diagenetic SEM | |
Unique Identification: Rutile Site name: Little Harding Lake Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Apparent diagenetic rutile associated with altered mafic silicates, opaques and abundant organic matter Image Tags: diagenetic | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 5000.0 Submitted by: Mark Shapley Notes: Diagenetic rutile aggregate; composition by EDX Image Tags: diagenetic twinned SEM | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Unusually large titanium-bearing mineral grain from basal material underlying a tropical peatland. Peculiar grain shape appears to reflect paragenesis as a complex diagenetic aggregate. Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 6000.0 Submitted by: Mark Shapley Notes: Diageneitc rutile needles embedding phyllosilicate grain Image Tags: mica diagenetic twinned acicular elongate SEM | |
Unique Identification: Rutile Site name: Little Harding Lake Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Apparent diagenetic rutile associated with altered mafic silicates, opaques and abundant organic matter Image Tags: diagenetic | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Unusually large titanium-bearing mineral grain from basal material underlying a tropical peatland. Grains from this interval analyzed by energy dispersive xray spectrometry (EDX) show simple compositions near that of rutile (TiO2). Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 3000.0 Submitted by: Mark Shapley Notes: Diageneitc rutile needles embedding phyllosilicate grain Image Tags: mica diagenetic twinned acicular elongate SEM | |
Unique Identification: Rutile Site name: Lake Bosumtwi Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Rutile Site name: Lake Bosumtwi Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 5000.0 Submitted by: Mark Shapley Notes: Diagenetic rutile aggregate; composition by EDX Image Tags: diagenetic twinned | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 6000.0 Submitted by: Mark Shapley Notes: Diagenetic rutile aggregate; composition by EDX Image Tags: diagenetic elongate SEM | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 4000.0 Submitted by: Mark Shapley Notes: Diagenetic rutile aggregate, showing inter-penetrating twinned blades; composition by EDX Image Tags: diagenetic elongate acicular twinned SEM | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Common simple grain form of diagenetic TiO2, showing prismatic habit, very high relief and prominent cleavage. Grains from this interval analyzed by energy dispersive xray spectrometry (EDX) show simple compositions near that of rutile (TiO2). Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage prismatic | |
Unique Identification: Rutile Site name: Little Harding Lake Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Apparent diagenetic rutile associated with altered mafic silicates, opaques and abundant organic matter Image Tags: diagenetic | |
Unique Identification: Rutile Site name: Little Harding Lake Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Apparent diagenetic rutile associated with altered mafic silicates, opaques and abundant organic matter Image Tags: diagenetic | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Two high-relief titanium-bearing mineral grains (6 o'clock and 12 o'clock) from basal material underlying a tropical peatland. Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Rutile Site name: Mubwindi wetland Light type: Scanning Electron Micrograph Magnification: 4000.0 Submitted by: Mark Shapley Notes: Complex twinned aggregate of diagenetic rutile Image Tags: twinned elongate acicular diagenetic SEM | |
Unique Identification: Rutile Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Unusually large titanium-bearing mineral grain from basal material underlying a tropical peatland. Peculiar grain shape appears to reflect paragenesis as a complex diagenetic aggregate. Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Siderite Site name: not specified Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: twinned flared elongate Image Tags: none | |
Unique Identification: Siderite Site name: Mubwindi Swamp, Uganda Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Very fine twinned siderite and associated ferric oxides from a ferric tropical peatand. Siderite occurs as a high-purity deposit several cm thick. Birefringence is very high for grains of this size. Image Tags: diagenetic twinned high-birefringence colored | |
Unique Identification: Siderite Site name: not specified Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: twinned flared elongate Image Tags: none | |
Unique Identification: Siderite Site name: 'Snake Monster' Lake, OR (informal) Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Fine rhombic siderite embedded in amorphous organic matter. Image Tags: highly-birefringent rhombic diagenetic | |
Unique Identification: Siderite Site name: 'Snake Monster' Lake, OR (informal) Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Fine rhombic siderite embedded in amorphous organic matter. Image Tags: highly-birefringent rhombic diagenetic | |
Unique Identification: Siderite Site name: Mubwindi Swamp, Uganda Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Very fine twinned siderite and associated ferric oxides from a ferric tropical peatand. Siderite occurs as a high-purity deposit several cm thick. Image Tags: diagenetic twinned high-birefringence colored | |
Unique Identification: Slide Glass Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Slide Glass Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Slide Glass Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Sulfur Site name: Peten Itza Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: translucent high-birefringent yellow Image Tags: none | |
Unique Identification: Sulfur Site name: Peten Itza Light type: Cross-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: translucent high-birefringent yellow Image Tags: none | |
Unique Identification: Tephra Site name: Jones Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: glassy vesicular stretched Image Tags: none | |
Unique Identification: Tephra Site name: Jones Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: prominent mafic minerals typical of GP. mineral-rich Image Tags: none | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: basaltic tephra presumed to be from Craters of the Moon basaltic province Image Tags: basaltic mafic micro-tubule Pele's-Hair | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Shapley Notes: Quenched glassy rind coating euhedral feldspar grain Image Tags: feldspar volcanic-glass overgrowth tephra | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Shapley Notes: Glacier Peak(?) crystal-rich tephra Image Tags: tephra volcanic-glass crystalline mafic minerals | |
Unique Identification: Tephra Site name: Fish Light type: Cross-Polarized Light Magnification: 100 Submitted by: Mark Shapley Notes: In cross-polarized light, glassy quenched rind is invisible along grain margins, but visible as scaly texturing disrupting birefringence on the body of the amphibole grain. From an unidentified tephra occurrence on the Kenai Peninsula, Alaska. Image Tags: amphibole hornblende pleiochroic green prismatic quenched-rind mafic-mineral volcanic-glass | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Shapley Notes: Glacier Peak(?) crystal-rich tephra Image Tags: tephra volcanic-glass crystalline mafic minerals | |
Unique Identification: Tephra Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Mark Shapley Notes: Quenched magmatic rind (glassy) prominent in side view along grain margins. From an unidentified tephra occurrence on the Kenai Peninsula, Alaska. Image Tags: amphibole hornblende pleiochroic green prismatic quenched-rind mafic-mineral volcanic-glass | |
Unique Identification: Tephra Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: green vesicular | |
Unique Identification: Tephra Site name: Yellowstone Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: Highly vesicular volcanic shard Image Tags: vesicular | |
Unique Identification: Tephra Site name: Jones Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: analyzer <90 deg. glassy vesicular stretched Image Tags: none | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Shapley Notes: Quenched glassy rind coating euhedral feldspar grain Image Tags: feldspar volcanic-glass overgrowth tephra | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Shapley Notes: Glacier Peak(?) crystal-rich tephra Image Tags: tephra volcanic-glass crystalline mafic minerals | |
Unique Identification: Tephra Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of volcanic glass shards showing a wide range of shard morphology, including semi-regular fragments packed with subparallel pipe vesicles and vesicular glass fragments and bubble wall shards, foraminifera and large biotite mica flake also in the field., volcanic-glass pyroclastic pipe-vesicles shards Image Tags: none | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Shapley Notes: Glacier Peak(?) crystal-rich tephra Image Tags: tephra volcanic-glass crystalline mafic minerals | |
Unique Identification: Tephra Site name: Jones Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: prominent mafic minerals typical of GP. mineral-rich Image Tags: none | |
Unique Identification: Tephra Site name: Redfish Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: basaltic tephra presumed to be from Craters of the Moon basaltic province Image Tags: basaltic mafic micro-tubule Pele's-Hair | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Glacier Peak G Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: olivine, volcanic glass Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: volc glass, oxide coatings Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: volc glass lath or thread fragment ('Pele's hair'?), oivine(?), other mafics Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: olivine, volcanic glass Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: volc glass, oxide coatings Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: volc glass, magnetite, oxide coatings, mafic minerals, feldspars Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: volc glass lath or thread fragment ('Pele's hair'?), oivine(?), other mafics Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Tephra - mafic Site name: Redfish Lake Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: volc glass, magnetite, oxide coatings, mafic minerals, feldspars Image Tags: tephra volcanic-glass crystalline mafic minerals | |
Unique Identification: Tephra - Mount Saint Helens Y Site name: Wallowa Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra - Mount Saint Helens Y Site name: Wallowa Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra - Mount Saint Helens Y Site name: Wallowa Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra - Mount Saint Helens Y Site name: Wallowa Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra - Mount Saint Helens Y Site name: Wallowa Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra - Mount Saint Helens Y Site name: Wallowa Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra - Mt. St. Helens J Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Mt. St. Helens J Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Mt. St. Helens J Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Mt. St. Helens J Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Mt. St. Helens J Site name: Swiftcurrent Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra - Mt. St. Helens J Site name: Swiftcurrent Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Tephra- Mazama Site name: Pettit Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Titanite Site name: Medicine Lake, MT Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Titanium-bearing mineral phase from a late-Holocene dessication horizon in Medicine Lake, MT. Prominent birefringent colors are obscured by the strong dispersion of the high-density grain. Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Titanite Site name: Medicine Lake, MT Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Titanium-bearing mineral phase from a late-Holocene dessication horizon in Medicine Lake, MT. The extreme relief and acute twinning angle are characteristic of Ti oxides. Specimens from this interval analyzed by energy-dispersive Xray spectrometry (EDX) show complex compositions suggesting titanite (CaTiSiO5) rather than rutile (TiO2). Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Titanite Site name: Medicine Lake, MT Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Titanium-bearing mineral phase from a late-Holocene dessication horizon in Medicine Lake, MT. Prominent birefringent colors are obscured by the strong dispersion of the high-density grain. Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Titanite Site name: Medicine Lake, MT Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Titanium-bearing mineral phase from a late-Holocene dessication horizon in Medicine Lake, MT. The extreme relief and acute twinning angle are characteristic of Ti oxides. Specimens from this interval analyzed by energy-dispersive Xray spectrometry (EDX) show complex compositions suggesting titanite (CaTiSiO5) rather than rutile (TiO2). Image Tags: twinned heavy-mineral high-relief high-birefringence diagenetic cleavage | |
Unique Identification: Toothpick Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Toothpick Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Toothpick Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Toothpick Site name: not specified Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Toothpick Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Toothpick Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Toothpick Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Tourmaline Site name: Tanners Light type: Cross-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: prismatic blunt-ended faceted Image Tags: none | |
Unique Identification: Tourmaline Site name: Arthurs Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic | |
Unique Identification: Tourmaline Site name: Tanners Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: prismatic blunt-ended faceted Image Tags: none | |
Unique Identification: Tourmaline Site name: Arthurs Lake Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Tourmaline Site name: Arthurs Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic | |
Unique Identification: Tourmaline Site name: Arthurs Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: pleochroic | |
Unique Identification: Tourmaline Site name: Arthurs Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: none Image Tags: black euhedral | |
Unique Identification: Trona Site name: Owens Light type: Cross-Polarized Light Magnification: 100 Submitted by: Joe Smoot Notes: high birefringence, striated and acicular, monoclinic Image Tags: none | |
Unique Identification: Trona Site name: Owens Light type: Plane-Polarized Light Magnification: 100 Submitted by: Joe Smoot Notes: high relief, striated and acicular, monoclinic Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Cross-Polarized Light Magnification: 1000.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Plane-Polarized Light Magnification: 1000.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Twin Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Twin Lake Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Twin Lake Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Twin Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Plane-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Cross-Polarized Light Magnification: 200.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Turbidite sequence Site name: Pettit Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: none Image Tags: none | |
Unique Identification: Vivianite Site name: Triangle Lake Bog, Ohio Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Prismatic to tabular vivianite from a peatland in Ohio. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned vivianite fans in a matrix of diatom ooze. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: iron rich assemblage Image Tags: blue | |
Unique Identification: Vivianite Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: iron rich assemblage Image Tags: blue | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned vivianite fan in orientation near parallel to analyzer; most of the fan elements are near optical extinction. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned vivianite fans in a matrix of diatom ooze. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Val Stanley Notes: iron rich assemblage Image Tags: birefringent euhedral | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned bundles of acicular vivianite. Image Tags: pleiochroic blue twinned phosphate acicular diagenetic | |
Unique Identification: Vivianite Site name: Iceland Lake Light type: Plane-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: colored blue translucent euhedral cleavage monoclinic Image Tags: none | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned vivianite fans, showing the effects of orientation on optical behavior. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Spectacular twinned vivianite fan in a matrix of diatom ooze. Appearance of interference colors is altered by strong and variable mineral color. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Valles Caldera Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: none Image Tags: blue | |
Unique Identification: Vivianite Site name: Valles Caldera Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: atypical occurrence, near-pure vivianite. dissagregated-nodule Image Tags: none | |
Unique Identification: Vivianite Site name: Bay Horse Lake, Idaho Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Fine-grained, high-purity occurrence of vivianite, interpreted as an endogenic precipitate from waters rich in Fe(2+) and PO4(3-) - rich waters. Mineral occurrence is localized within lamellae in late-Pleistocene glaciolacustrine sediments. Pleiochroism maximizes color in near-parallel (vertical) grain orientations. Image Tags: phosphate pleiochroic diagenetic ferrous blue prismatic endogenic | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned bundles of acicular vivianite showing pleiochroic effects of grain orientation; major axis of the twinned aggregate is nearparallel to polarizer and shows maximum color. Image Tags: pleiochroic blue twinned phosphate acicular | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned bundles of acicular vivianite. Image Tags: pleiochroic blue twinned phosphate acicular | |
Unique Identification: Vivianite Site name: Twin Light type: Plane-Polarized Light Magnification: 400x Submitted by: Amy Myrbo Notes: none Image Tags: none | |
Unique Identification: Vivianite Site name: Iceland Lake Light type: Cross-Polarized Light Magnification: 630 Submitted by: Michael Rosen Blas Valero Notes: colored blue translucent euhedral cleavage monoclinic Image Tags: none | |
Unique Identification: Vivianite Site name: Bay Horse Lake, Idaho Light type: Plane-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Spectacular occurrence of large, bladed vivianite in organic-poor late Pleistocene glaciolacustrine sediments. The 3-mm nodule appears black in the split and oxidized core face. Close to 100% of material in the field of view is vivianite. Image Tags: phosphate pleiochroic diagenetic ferrous blue bladed | |
Unique Identification: Vivianite Site name: Bay Horse Lake, Idaho Light type: Cross-Polarized Light Magnification: 100.0 Submitted by: Mark Shapley Notes: Spectacular occurrence of large, bladed vivianite in organic-poor late Pleistocene glaciolacustrine sediments. This is an unusual case where large grain size renders vivianite birefringence prominent. Image Tags: phosphate pleiochroic diagenetic ferrous blue bladed | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned vivianite fans, showing the effects of orientation on optical behavior. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Bay Horse Lake, Idaho Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Fine-grained, high-purity occurrence of vivianite, interpreted as an endogenic precipitate from waters rich in Fe(2+) and PO4(3-) - rich waters. Mineral occurrence is localized within lamellae in late-Pleistocene glaciolacustrine sediments. Image Tags: phosphate pleiochroic diagenetic ferrous blue prismaticendogenic | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned bundles of acicular vivianite showing pleiochroic effects of grain orientation; major axis of the twinned aggregate is near perpendicular to polarizer and shows minimal color. Image Tags: pleiochroic blue twinned phosphate acicular | |
Unique Identification: Vivianite Site name: Triangle Lake Bog, Ohio Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Prismatic to tabular vivianite from a peatland in Ohio. Unusual orthogonal twinning accentuates pleiochroism in plane-polarized light. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Valles Caldera Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: atypical occurrence, near-pure vivianite. dissagregated-nodule Image Tags: none | |
Unique Identification: Vivianite Site name: Triangle Lake Bog, Ohio Light type: Cross-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Prismatic to tabular vivianite from a peatland in Ohio. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Spectacular twinned vivianite fan in a matrix of diatom ooze. Pleiochroism is highlighted by the fan geometry, showing dependence of color on orientation. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Lake Challa, Tanzania Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Twinned vivianite fan in orientation near parallel to analyzer; density of color in plane-polarized light is maximized. Matrix of isotropic diatom frustules. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: Triangle Lake Bog, Ohio Light type: Plane-Polarized Light Magnification: 630.0 Submitted by: Mark Shapley Notes: Prismatic to tabular vivianite from a peatland in Ohio. Unusual orthogonal twinning accentuates pleiochroism in plane-polarized light. Image Tags: pleiochroic blue twinned phosphate diagenetic | |
Unique Identification: Vivianite Site name: not specified Light type: Plane-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Vivianite Site name: not specified Light type: Cross-Polarized Light Magnification: not specified Submitted by: not specified Notes: none Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake Light type: Scanning Electron Micrograph Magnification: 2500.0 Submitted by: Mark Shapley Notes: Vesicular glass fragment from a basaltic tephra originating in the Snake River Plain, Idaho. Vesicles will give this isotropic grain a dark, high-relief appearance in plane-polarized light through the petrographic microscope. Image Tags: SEM volcanic_glass pumice vesicular | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Mt. St. Helens 'Y' series(?) tephra Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Mt. St. Helens 'Y' series(?) tephra Image Tags: isotropic | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake Light type: Scanning Electron Micrograph Magnification: 1500.0 Submitted by: Mark Shapley Notes: Dense, conchoidally fractured glass fragment from a basaltic tephra originating in the Snake River Plain, Idaho. This material is optically isotropic, but colored in plane-polarized light through the petrographic microscope. Image Tags: SEM volcanic_glass conchoidal conchoidal_facture ash | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Partially altered volcanic glass from a basaltic tephra originating in the Snake River Plain, ID. Birefringent alteration is localized along a tubule in the glass fragment. Image Tags: volcanic-glass low-birefringent zeolite alteration | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Partially altered volcanic glass from a basaltic tephra originating in the Snake River Plain, ID. Altered regions (palagonitized?) are yellowish and localized preferentially on vesicle walls. Image Tags: volcanic-glass low-birefringent zeolite | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra Image Tags: isotropic conchoidal | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Sharp vesicular shard of basaltic glass originating in the Snake River Plain, Idaho. Small altered show as birefringent patches. Image Tags: volcanic-glass alteration vesicular isotropic zeolite | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake Light type: Scanning Electron Micrograph Magnification: 6000.0 Submitted by: Mark Shapley Notes: High-magnification view of dense glass fragment from a basaltic tephra originating in the Snake River Plain, Idaho, showing stretched texture and cooling fractures. Image Tags: SEM volcanic_glass conchoidal conchoidal_facture ash | |
Unique Identification: Volcanic Glass Site name: Jones Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: glassy vesicular stretched Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra; vesicular pumice fragment. Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Highly vesicular (pumaceous) volcanic glass from a basaltic tephra originating in the Snake River Plain, Idaho. Vesicles give colorless glass an opaque appearance in plane-polarized light. Image Tags: volcanic-glass vesicular bubbles dark isotropic | |
Unique Identification: Volcanic Glass Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: volcanic glass shard with bubble junctions still intact Image Tags: vesicular volcanic | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Sand-sized vesicular glass from a basaltic tephra originating in the Snake River Plain, Idaho. Most of the glass is fully extinct in cross-polarized light. Image Tags: volcanic-glass vesicular isotropic greenish-brown dark | |
Unique Identification: Volcanic Glass Site name: Lewis Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: shard morphologies Image Tags: pyroclastic | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra; vesicular pumice fragment. Image Tags: vesicular pumice | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Sharp vesicular shard of basaltic glass originating in the Snake River Plain, Idaho. Small altered regions appear brown or yellowish. Image Tags: volcanic-glass alteration vesicular isotropic zeolite | |
Unique Identification: Volcanic Glass Site name: Redfish Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Basaltic tephra, probably from the Snake River Plain. Fine mineral inclusions in vesicle. Image Tags: mafic_tephra colored vesicular inclusions isotropic | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra Image Tags: conchoidal isotropic | |
Unique Identification: Volcanic Glass Site name: Tyrrhenian Sea, Mediterranean Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Field of volcanic glass shards showing a wide range of shard morphology, including semi-regular fragments packed with subparallel pipe vesicles and vesicular glass fragments and bubble wall shards, volcanic-glass pyroclastic pipe-vesicles shards Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Partially altered (palagonitic?) volcanic glass from a basaltic tephra originating in the Snake River Plain, Idaho. Altered regions show yellowish-brown discoloration of near-colorless fresh glass. Image Tags: volcanic-glass low-birefringent zeolite alteration | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Highly vesicular (pumaceous) volcanic glass from a basaltic tephra originating in the Snake River Plain, Idaho. Almost wholly isotropic in cross-polarized light. Image Tags: volcanic-glass vesicular bubbles dark isotropic | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Concoidally fractured, strongly colored volcanic glass from a basaltic tephra originating in the Snake River Plain, Idaho. Insect wing to the right provides textural aesthetic counterpoint. Image Tags: conchoidal-fracture volcanic-glass dark isotropic | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Partially altered volcanic glass from a basaltic tephra originating in the Snake River Plain, ID. Altered regions (palagonitized?) are yellowish-brown. Image Tags: volcanic-glass low-birefringent zeolite alteration | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Mt. St. Helens 'Y' series(?) tephra Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Mt. St. Helens 'Y' series(?) tephra Image Tags: vesicular isotropic | |
Unique Identification: Volcanic Glass Site name: Pettit Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Glacier Peak 'G'(?) tephra Image Tags: isotropic conchoidal | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Partially altered (palagonitic?) volcanic glass from a basaltic tephra originating in the Snake River Plain, Idaho. Altered regions show diffuse, low-order birefringence. Image Tags: volcanic-glass low-birefringent zeolite alteration | |
Unique Identification: Volcanic Glass Site name: Evans Lake Light type: Plane-Polarized Light Magnification: not specified Submitted by: Andy Breckenridge Notes: volcanic ash, tephra Image Tags: none | |
Unique Identification: Volcanic Glass Site name: Redfish Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Basaltic tephra, probably from the Snake River Plain. Fine mineral inclusions in vesicle. Image Tags: mafic_tephra colored vesicular inclusions isotropic | |
Unique Identification: Volcanic Glass Site name: Yellowstone Light type: Plane-Polarized Light Magnification: 630 Submitted by: Val Stanley Notes: Note aligned mineral inclusions Image Tags: mineral-inclusions | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Partially altered volcanic glass from a basaltic tephra originating in the Snake River Plain, ID. Altered regions (palagonitized?) are weakly birefringent. Image Tags: volcanic-glass low-birefringent zeolite | |
Unique Identification: Volcanic Glass Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Sand-sized vesicular glass from a basaltic tephra originating in the Snake River Plain, Idaho. Grain at lower right is dark in plane-polarized light, while grain in upper left quadrant appears colorless. Image Tags: volcanic-glass vesicular isotropic greenish-brown dark | |
Unique Identification: Zircon Site name: Woods Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: elongate high-relief | |
Unique Identification: Zircon Site name: Hell Roaring Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Occurrence in sand composed largely of reworked Mazama Ash. Striking zoning indicates multiple growth phases in magma chamber. Image Tags: euhedral zoned inclusions heavy_mineral | |
Unique Identification: Zircon Site name: Bay Horse Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Large prismatic zircon from a basaltic tephra originating in the Snake River Plain, Idaho. The brilliant birefringence is characteristic of the mineral in all sizes. Image Tags: high-birefringence high-relief transparent mafic_tephra prismatic | |
Unique Identification: Zircon Site name: South of Java Trench, NE Indian Ocean (9 46.53 SA, 102 41.95E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Prismatic subeuhedral zircon crystal. Note the very high relief. Mica and broken pyroxene crystal fragments also in the field. , mica pyroxene Image Tags: none | |
Unique Identification: Zircon Site name: Woods Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: elongate high-relief | |
Unique Identification: Zircon Site name: Hell Roaring Lake, ID Light type: Cross-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Occurrence in sand composed largely of reworked Mazama Ash. Striking zoning indicates multiple growth phases in magma chamber. Image Tags: euhedral zoned inclusions heavy_mineral | |
Unique Identification: Zircon Site name: South of Java Trench, NE Indian Ocean (9 46.53 SA, 102 41.95E) Light type: Plane-Polarized Light Magnification: not specified Submitted by: Guy Rothwell Notes: Prismatic subeuhedral zircon crystal. Note the very high relief., Image Tags: none | |
Unique Identification: Zircon Site name: Woods Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: hexagonal | |
Unique Identification: Zircon Site name: Woods Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: elongate high-relief | |
Unique Identification: Zircon Site name: Bay Horse Lake, ID Light type: Plane-Polarized Light Magnification: 400.0 Submitted by: Mark Shapley Notes: Large prismatic zircon from a basaltic tephra originating in the Snake River Plain, Idaho. The extreme relief of the mineral accentuates the intersection of prism faces as shadowed lines. Note prismatic inclusion oriented to the long axis of the zircon. Image Tags: high-birefringence high-relief transparent mafic_tephra prismatic | |
Unique Identification: Zircon Site name: Woods Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: elongate high-relief | |
Unique Identification: Zircon Site name: Woods Lake Light type: Plane-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: hexagonal | |
Unique Identification: Zircon Site name: Woods Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: elongate high-relief | |
Unique Identification: Zircon Site name: Woods Lake Light type: Cross-Polarized Light Magnification: 400 Submitted by: Val Stanley Notes: characteristic shape Image Tags: elongate high-relief | |
Unique Identification: Zorbitrol Site name: not specified Light type: Plane-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Zorbitrol Site name: not specified Light type: Cross-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Zorbitrol Site name: not specified Light type: Cross-Polarized Light Magnification: 100 Submitted by: Jess Rodysill Notes: none Image Tags: none | |
Unique Identification: Zorbitrol Site name: not specified Light type: Plane-Polarized Light Magnification: 400 Submitted by: Jess Rodysill Notes: none Image Tags: none |
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