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Heavy mineral sands are exploited in several locations around the world and it is known that they often contain naturally occurring radionuclides of uranium and thorium radioactive series.Heavy mineral sands from the littoral of Mozambique in the Indian Ocean are exploited for rutile and garnet production.Ambient radiation doses were measured and samples collected for quantitative determination of radionuclide concentrations.Beach sands from the deposits at the coast and samples of mineral fractions after separation by gravity,magnetic,and electric properties were analyzed in the laboratory for alpha and gamma emitting radionuclides.Concentrations of radionuclides and radiation doses are presented and discussed in detail.For example,in beach sands such as collected at the mining area concentrations of 238U and 232Th were 70±2 Bq/kg dry weight (dw) and 308±9 Bq/kg (dw),respectively,while after minerals separation the radionuclide concentrations in rutile-zircon fraction were 2240±64 and 6125±485 Bq/kg (dw),for the same radionuclides.Both uranium (238U) and thorium (232Th) radioactive decay series were in near secular radioactive equilibrium in these minerals.Other mines in the country,such as tantalite and bauxite mines were visited also and samples of materials analyzed for naturally co-occurring radionuclides and results are reported herein.Local populations living in the mining areas assessed for radioactivity,in general are not exposed to materials with high radionuclide concentrations and to significantly enhanced radiation doses.However,some of the separated minerals,such as zircon and tantalite,contain high uranium and thorium concentrations and in minerals storage areas the external radiation doses may exceed recommended radiation dose limits for members of the public (1 mSv/y).This requires implementation of radiation protection measures for the radiological safety of workers.The need for radiation control measures is discussed.