On this page you will find details on how participating in Viewing the Rock World project works, how the slide viewer works, and resources on how polarised light microscopy works.
As the project develops, I will build more content on the mechanics and physics of how the polarised thin section viewer works.
Printing and using the viewer
This project is no longer in a “get involved” phase, so there’s no traveling thin section collection to join. At this point, anyone interested simply 3D prints the Viewing the Rock World viewer themselves to keep the project alive.
This still lets you experience an element of Earth Science research without any expensive equipment, and building the device introduces concepts in physics and electromagnetism relating to polarised light microscopy. I’m still thrilled to hear about people building and using it, so if you print one, please get in touch and let me know how it went. I love receiving updates: matthew.tarling@ubc.ca.
How the thin section viewer works
The thin section viewer consists of two crossed linear polarising filters that rotate together relate to the thin section inserted within.
It works on the same sets of principles as cross-polarised light microscopy. The polarising films alter the properties of the light, only allowing certain orientation of the waves that make up light to pass. In the thin section viewer, the two polarising filters are crossed in such a way that ALL light is blocked, this is why when there is no thin section inserted the viewer is dark. When you insert a thin section, the waves of light become altered by the passage through the thin slice of rock, creating new colours which depend on the orientation of the minerals relative to the polarisers. This is why the colours change as you rotate the polarisers.
For more detail on how microscopy of rocks and minerals works, check out these fantastic videos by GEO GIRL.