Scientists have claimed to have found uranium deposits in the icy heights of Ladakh but the Department of Atomic Energy has adopted a cautious approach regarding the commercial importance of the find.

Geologists from the Kumaun University have found "exceptionally high concentration" of uranium and thorium in Udmaru, a small village situated on a volcanic rock formation in the Nubra-Shyok valley in northern Ladakh.

A preliminary study of a thick granite dyke showed that it contained abundant, small-to-medium grained euhedral, greenish coloured zircon, Rajeev Upadhyay, a geologist at the Nainital-based Kumaun University said in a communication in the latest issue of Current Science.

"Geochemical analysis of the separated zircon grains showed exceptionally high concentration of both uranium and thorium," he said.

Rock samples analysed in isotope laboratory of the University of Tuebingen in Germany [Images] have revealed uranium content to be as high as 5.36 per cent compared to around 0.1 per cent or less in ores present elsewhere in the country.

However, S K Malhotra, Head, Public Awareness Division, DAE said the finding was based on a "very small sample size (sub milligram) of zircon separated from the main ore body."

"In exploration carried out by Atomic Minerals Directorate of the DAE we have to explore a large area and establish the size of the ore body with average uranium content.

It is only after such estimates it is decided whether the deposit is of commercial interest," he said.

Malhotra said the finding could be of commercial interest only if large quantities running into thousands of tonnes are indicated and that too after proper chemical and physiso-chemical characterisation of the ore.

Upadhyay tested separated zircon samples weighing between 0.0192 milligrams and 0.0103 milligrams at the German laboratory under the aegis of the Alexander von Humboldt Fellowship.

India has an estimated 1.07 lakh tonnes of identified raw uranium reserves in the form of uranium oxides or yellow cake. The mineral is mostly found in the form of triuranium

octaoxide (U3O8).

A majority of the resources are found in the uranium provinces of Singhbhum (Jharkhand), Mahadek (Meghalaya) and Kadapa (Andhra Pradesh).

The DAE has embarked upon ambitious plans of exploration for uranium and deployment of new exploration techniques to augment uranium reserves even further. This includes opening up of new mines and setting up of new processing plants.

The new mines at Banduhurang and Turamdih and the processing mill at Turamdih have been commissioned, and would add to the uranium production in a short time.

Efforts are underway to augment the uranium resource base of the country by expediting exploration inputs in various geological domains.

In India, a number of Proterozoic basins (dating between 2,500 to 542 million years ago) such as Kadapa basin, Aravalli-Delhi fold belt, Gwalior-Vindhyan basin, Bhima basin, Karnataka, Chhattisgarh basin exist where multi-disciplinary investigations have been taken up in search of uranium deposits, official sources said.

In the Singhbhum uranium province, mining and exploration activities are being carried out in Jaduguda, Narwapahar, Turamdih, and Bagjata. The other deposits in this belt are Mohuldih, Nandup, Rajgaon, and Garadih, they said.

The Mahadek province contains the largest and richest sandstone-hosted uranium deposit of the country at Domiasiat in the West Khasi Hills district. Another deposit of similar nature is at Wahkyn where exploration activities are in progress.

The Kadapa province contains the Proterozoic unconformity related uranium deposit at Lambapur-Peddagattu in Nalgonda district, the sources said.

The region also hosts a unique stratabound uranium deposit at Tummalapalle, where a uranium mine and a processing plant is being commissioned in the next 36 months. The union cabinet approved the project last week.