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Geological materials usually contaminated with naturally occurring radioactive materials (NORM) have become a focus of great attention. The radioactivity concentrations of Ra-226, Th-232 and K-40 in some ornamental stones in Egypt, were measured using a high-resolution gamma ray spectrometer. The natural radionuclide contents, (Ra) equivalent activities and various hazard indices were also calculated to assess the radiation hazard. It was found that none of the results exceed the recommended limit value. All samples under investigation are within the recommended safety limit and do not pose significant radiation hazards.