In a petrographic microscope, the light is first polarized, then the thin section is placed in that beam of light and then that light passes through a second polarizer. A weird thing happens to ...

In a petrographic microscope, the light is first polarized, then the thin section is placed in that beam of light and then that light passes through a second polarizer.

Petrographic microscope image. Plane-polarized transmitted light photomicrograph of a thin section showing detail of cement paste. The image was taken at 200x magnification.

Eyjafjallajökull ash under a petrographic microscope in crossed-polarized light at ~40x. Image by Erik Klemetti. In this image, I've tried to identify the minerals in the ash.

This isn't a normal microscope, but a petrographic microscope that utilizes the special optical properties of minerals cut thin, down to ~30 microns thick (we call them "thin sections").

Petrological microscope: This new lab is equipped with a Leica DM750P petrographic microscope with transmitted and reflected light capabilities. A 2.5 megapixel MC120 HD camera is attached to the ...

The audience favorite, chosen by a March Madness-style bracket on UChicago’s social media channels, is “Fuchsia Bone,” a photograph of a fossil whale bone through a microscope taken by geophysical ...