Occurrence of kornerupine-bearing granulite from Kunjan locality, Salem district, Tamil Nadu, India

Kornerupine, although a rare mineral, has been reported from several locations around the world in various types of aluminomagnesian Proterozoic rocks subjected to amphibolite and granulite facies metamorphism. Here we report the occurrence of kornerupine in quartzo-feldspathic gneisses near Kunjan town located in the southwestern part of Salem district, Tamil Nadu, India. These kornerupine granulites show well-preserved retrogression texture, involving hydration reactions which helped develop the various mineral assemblages. The common stable assemblage in these granulites is orthopyroxene–cordierite–kornerupine–biotite–spinel–K-feldspar–plagioclase. The P–T conditions of these granulites have been derived using the winTWQ program, which gives results of ~800°C and ~6 kbar for kornerupine-bearing assemblage. The high P–T assemblage reported from this area bears a significant relationship with the metamorphic history and exhumation of the Salem–Namakkal block