Study on uranium distribution in ore samples of Nong Son Basin (Viet Nam)

Geological studies show that uranium ore bodies in Nong Son basin (Quang Nam province, Viet Nam) are lens, chain of lenses with uranium content of U3O8 ≥ 0.01%. In one bed of uranium bearing rock, the uranium contents widely vary from 0.001 to 0.675%. Knowledge of the uranium distribution in mined ore is very important for preconcentration processes. The study has conducted classification by radioactivity measurement for each ore grain (size of 25-200 mm) and determine uranium content in respective ore sample. To determine radioactivity, gamma spectrometer (thallium- activated sodium iodide crystals NaI(Tl) 80x80 mm and multi-channel analytical system of model MCA-2003-001,VNEC) were used. Uranium contents were determined by coloriphotometry (Spectronic 20 D+, USA). Based on the results obtained from the study of uranium distribution in ore samples of the above area it was concluded that (1) the uranium distribution levels are not even in the studied ore samples and (2) it is possible to use radiometric sorting to enrich ores from Nong Son basin