This web site includes almost 200 photomicrographs of rocks and minerals. The thin sections are all in transmitted white light, some in plane polarized light, but most with crossed polarizers on. The majority of the pictures show a field of view 1.5 mm long (about 80X magnification). Other magnifications are indicated where different. The thin sections are categorized into minerals, igneous, metamorphic, and sedimentary rocks, and textures. Each thin section has a caption explaining the sample either by optical properties, occurrence, or other features. This resource is part of the Teaching Petrology collection. http://serc.carleton.edu/NAGTWorkshops/petrology03/index.html Educational levels: Graduate or professional, Undergraduate lower division, Undergraduate upper division
