inorganic chemistry and its application

REE concentrations are homogeneous in individualpigeonite and plagioclase grains of equilibrated eucrites but,except for Ibitira which is highandly equilibrated, showintergrain variations. REE zoning was observed in somepyroxene and plagioclase grains of Pasamonte and ALHA۷۶۰۰۵(two polymict eucrites with high abundance of unequilibratedclasts) and in some plagioclase grains of Sioux CountyChervony Kut (two equilibrated eucrites).