These are uranium, thorium, radium, lithium etc. Monazite is the main source of thorium.
It is found in Jharkhand, Himalayas, Rajasthan and Andhra Pradesh.
The Monanzite sand of Kerala coast is the major source of uranium, in the copper belt of Jharkhand state, in the Aravallis in Rajasthan.
The sands of Quilon and Palghat of Kerala, in Kanya Kumari district of Tamil Nadu, Mica mines of Gaya (Bihar), Nellore (Andhra Pradesh), Udaipur and Jaipur (Rajasthan) are other sources of uranium. The production of uranium takes place in the mines at Jaduguda in Singhbhum district of Jharkhand state.
Thorium is called the future substitute for Uranium to be used in fast breeder reactors because the exhaustion of Uranium ore will push man to exploit Thorium. Even now, Thorium ore is being used in many countries.
Thorium is a soft radioactive metallic element. It belongs to Actimide series of elements. It was discovered in 1848 by a famous Swedish Chemist Berzelius who named this element after a Norse god Thor.
It is a ductile mineral and melts at 1750°C. Its half life Period is L39 X 1010 years. Around 13 different types of isotopes of Thorium are available. Occurrence of Thorium is more than that of Uranium. Hence Thorium presents a tremendous potential of nuclear energy.
Uses of Thorium.
(i) It is used as a good nuclear fuel; (ii) It is nowadays used in electronic instruments. (Hi) Nuclear medicines are also making use of this substance. (iv) It is also used as analytic agent, (v) It is also used for producing high temperature ceramics and optical glasses.
Occurrence of Thorium.
It constitutes 0.001 to 0.002% of earth’s crust.
Its ores are as follows:
(i) Monazite, (ii) Thorite, (iii) Thorianite
The rich deposits of thorium are found in India in Kerala state in the sand near the Arabian Sea coast.