Andesite thin section microscope slide exhibiting an intermediate, fine grained groundmass with occasional phenocrysts of plagioclase feldspar.This material was collected from Borrowdale in the Lake District, UK & is of Late Ordovician age. The glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy, petrography and educational use.
An andesite slide, a volcanic rock found in the Andes Mountains of South America. It has an intermediate, fine-grained groundmass and occasional phenocrysts of plagioclase feldspar. Andesite is an extrusive rock with a composition between rhyolite and basalt. It is similar to diorite and contains 52-63% silica, as well as pyroxene (augite) and feldspars (plagioclase). Andesite lava has moderate viscosity, resulting in thick lava flows and domes. This sample was collected from Borrowdale in the Lake District, UK, and is from the Late Ordovician period. The glass andesite slide measures 46 x 27 mm and comes with a protective card sleeve and label, making it ideal for microscopy, petrography, and education.