These are some images of thin sections of terrestrial rocks.

These photos were taken through an Olympus CH-2 modified for cross-polarising work. I’m quite new to this, so my identification of minerals should be taken with a pinch of salt. The wider thumbnails lead to a side-by-side image of the specimen in plane polarised and cross-polarised light. Some of the images are a little burnt-out, I need to experiment further with camera settings (and cameras) to nail this.


From Ayrshire, Scotland. This slide contains plenty olivine, brightly coloured and with random cracks, alongside the straight, black-and-white plagioclase crystals.



Collected from a lahar of the Soufriere volcano, this is rich in hornblende with inclusions and various feldspars.



Ardnamurchan, Scotland. Rich in pyroxenes, plagioclase, biotite and magnetite (the black areas).



Roche, Cornwall. This rock consists mainly of tourmanline crystals in quartz. The tourmaline is highly coloured in XPL.