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In this blog, we're taking you into the journey of thin section photos that were captured and given by students and young professionals from Finland, Ireland, Denmark, Czech Republic and Plymouth (UK).
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Note: We are using following thin section photos by having permission from their owners. If you like to use these photos, leave us a message or email us here.
1. A beautiful heart shaped hornblende in XPL (cross polarized light) view.It is a thin section of basalt with some secondary mineralization in the vesicles. Plagioclase is present in the form of black and white matrix and large phenocryst (with some zoning). Alignment of plagioclase grains is indicative of the "flow" of magma.
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Photo Credits: Astaley |
2. Thin Section of a Biotite and Muscovite, XPL view
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Photo Courtesy: Laura |
3. Thin Section of a Plagioclase (orthoclase) and Pyroxene, XPL
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Photo Courtesy: Laura |
4. Eclogite in Thin Section, XPL
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Photo Courtesy: Laura |
5. Cummulate Rock with Pyroxene and plagioclase, XPL
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Photo Courtesy: Laura |
6. Blueschist, XPL

Photo Courtesy: Laura
7. Agglomerate in a Thin Section, XPL view
Agglomerates are pyroclastic igneous rocks that consist almost wholly of angular or rounded lava fragments of varying size and shape. Fragments are usually poorly sorted in a tuffaceous matrix, or appear in lithified volcanic ash. (Britannica.com)

Photo Courtesy: Laura
8. Thin Section of a Pigeonite and Olivine, XPL

Photo Courtesy: Laura
9. Olivine phenocryst in Basaltic Lapilli, XPL

Photo Courtesy: Laura
10. Thin Section of a Gabbro, XPL
Showing minerals; Pyroxene and Olivine, plagioclase and others. Learn more about Gabbro here.

Photo Courtesy: Laura
11. Another beautiful thin section of a Gabbro, XPL

Photo Courtesy: Laura
12. Thin Section of a Greenschist, XPL

Photo Courtesy: Laura
13. Thin Section showing intrusion of rocks from magma chamber into country rocks, XPL

Photo Courtesy: Jack Lewis Donnelly
14. Thin Section of a Sillimanite - a mineral found in rocks formed by the metamorphism of a mudstone. (XPL view)

Photo Courtesy: Jack Lewis Donnelly
15. Microgeode in ultrabasic vulcanite (a rare copper telluride mineral), 30 µm thin section, PPL and XPL

Photo Courtesy: Petr Hyks










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Photo Courtesy: Petr Hyks
See original photo here
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16. Muscovite & biotite (30 µm thin section, PPL and XPL)
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Photo Courtesy: Petr Hyks |

Photo Courtesy: Petr Hyks
Same photo in XPL view. See original photo here

Same photo in XPL view. See original photo here
17. Quartz and epidote (30 µm thin section, PPL and XPL)

Photo Courtesy: Petr Hyks

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Photo Courtesy: Petr Hyks
See original here.
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18. Olivine (30 µm thin section, PPL and XPL)
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Photo Courtesy: Petr Hyks See this photo here on Petr Hyks' website |
19. Zircons in biotite (30 µm thin section, PPL views, showing extinction)
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Photo Courtesy: Petr Hyks See this photo here on Petr's website |
20. Zircon in biotite (30 µm thin section, XPL)

Photo Courtesy: Petr Hyks
See this photo here on Petr's website

See this photo here on Petr's website
21. Kyanite surrounded by muscovite (30 µm thin section, PPL and XPL)
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Photo Courtesy: Petr Hyks See these photos on Petr's page here and here |
22. Zircon crystal in chloritized biotite (30 µm thin section, PPL and XPL)

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Photo Courtesy: Petr Hyks See these photos on Petr's page here and here |
23. Thin Section of Olivine Diabase in XPL and PPL view.
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Photo Courtesy: GeoAmethyst |
24. Thin Section of Basalt in XPL view
Having minerals: Olivine (in center) plagioclase, pyroxene and other accessory minerals
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Photo Courtesy: GeoAmethyst |
25. Thin Section of a Trachyte, XPL view
Trachyte is an igneous volcanic rock with aphanitic to porphyritic texture. It is volcanic equivalent of Syenite. Major or essential minerals are alkali feldspar with less amount of plagioclase, quartz or feldspathiod.
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Photo Courtesy: GeoAmethyst |
26. Thin Section of a Harzburgite, XPL view
Harzburgite is an ultramafic igneous rock. It chiefly contains plagioclase (under 10%) , olivine, orthopyroxene (enstatite), clinopyroxene (diopside) and biotite. There could be a small amount of talc, carbonate, tremolite, cummingtonite, chlorite, serpentine and titanite.
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Photo Courtesy: GeoAmethyst |
27. Another thin section of Harzburgite, XPL view
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Photo Courtesy: GeoAmethyst |
28. Thin Section of Pyroxenite (an ultramafic igneous rock), XPL view
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Photo Courtesy: GeoAmethyst |
29. Thin Section of Trachyte showing Sandine mineral in center, XPL view

Photo Courtesy: GeoAmethyst
30. Thin Section of Andesite, XPL view
It is an extrusive igneous, of intermediate composition, with aphanitic to porphyritic texture. Here this thin section is showing chiefly hornblende and plagioclase.

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Photo Courtesy: GeoAmethyst |
31. Thin Section of Alkali Basalt (silica undersaturated) in XPL view.
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Photo Courtesy: GeoAmethyst |
32. Thin Section showing small clinopyroxene grains within orthopyroxene

Photo Courtesy: GeoAmethyst

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Useful Websites:
1. Polarized light Microscopy (Image Gallery)2. How to make a thin section
3. Petrographic thin section preparation
4. Guide to Thin Section Microscopy
5. Index of Minerals in Thin Section
6. Optical Petrography website by an Italian Geologist
7. Carbonate Thin Section Images and Exercises