To perform a point count using the Gazzi-Dickinson method, a randomly selected thin section from a sedimentary rock is needed, with a slide advance mechanism that will randomly select points on the slide with a petrographic microscope.
22.
"' Hyalopilitic "'is a groundmass, which is visible only under magnification with a petrographic microscope, that contains a mixture of very fine-grained mineral crystals either mixed with natural volcanic glass, or surrounded by thin bands of volcanic glass.
23.
In an optical mineralogy analysis, petrologists analyze thin sections of rock samples using a petrographic microscope, where the minerals can be identified through their different properties in plane-polarized and cross-polarized light, including their birefringence, pleochroism, geochemical evolution of rock units.
