Template:POTD/2022-01-03
In optical mineralogy and petrography, a thin section is a thin slice of a rock, mineral, soil, pottery, bones, or even metal sample, prepared in a laboratory, for use with a polarizing petrographic microscope, electron microscope and electron microprobe. A thin sliver of rock is cut from the sample with a diamond saw and ground optically flat. It is then mounted on a glass slide and then ground smooth using progressively finer abrasive grit until the sample is only 30 micrometres (0.0012 in) thick. This image shows a thin section of Siilinjärvi apatite ore from Finland in cross-polarized transmitted light; the specimen depicted here is approximately 36.6 mm (1.44 in) wide by 20 mm (0.79 in) high.Photograph credit: Kallerna