Dunite Peridotite thin section microscope slide. In XPL view these thin sections exhibit the bright and beautiful second order interference colours of olivine. The high relief, lack of cleavage and distinctive fracturing is clearly evident in PPL view making for a very attractive thin section. Dunite is the Olivine rich end member of the Peridotite group typically containing over 90% with minor amounts of Pyroxene, Chromite , Magnetite & Pyrope. It is a major constituent of mantle rock forming above a depth of 400 km. Dunite is rarely found within continental rocks except where associated with the basal sequences of ophiolites in subduction zones where mantle slabs have been thrust up into the continental crust during island arc collisions (orogeny). This material was collected from Åheim in Norway by staff. The glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy and educational use.