Reverse zoning between myrmekite and albite in a quartzofeldspathic gneiss from Broken Hill, New South Wales

Abstract
SummaryGrain boundary migration and the exsolution of albite from alkali feldspar, followed by the precipitation of myrmekite from the same source on to adjacent plagioclase grains, will explain the reversed zoning of these phases in contrast to the normal zoning seen in igneous rocks.