Thorium-rich monazites from the beach sands of Kalingapatnam-Baruva coast, Andhra Pradesh, east coast of India

Of the five microprobe analyses of monazites, one shows a very high concentration of ThO2 (30.81%) and relatively high Ca and low LREE (Ce, Nd, La, Pr, Sm) indicating that it is a cheralite variety of monazite. The other four monazites also show high concentration of ThO2 ranging from 12.30 to 15.89. Charnockites and pegmatites occurring in the drainage basin of the hinterland are the source rocks for the monazites. The monazites have an obvious bearing on the economic potential of these sands in exploring them along with the other associated heavy minerals like ilmenite, garnet, sillimanite and zircon. (author)