A radiological study of some ornamental stones: the bluish granites from Extremadura (Spain)

D. Pereira, L. Neves, A. Pereira, M. Peinado, J. A. Blanco, J. J. Tejado
2012 Natural Hazards and Earth System Sciences  
In the area of Trujillo (Extremadura, Spain) we have found a variety of striking bluish and secondary yellow granites outcropping within the Plasenzuela pluton. They are all quarried under different names and are characterized by leucocratic minerals in which a bluish phosphate is dispersed throughout the rock. Their physical and mechanical properties make these granites a perfect option for most applications as ornamental rocks. Within the pluton the radiological background is fairly
more » ... is fairly homogeneous, with no significant differences between the gamma ray fluxes of the different facies. U (6.4 ± 0.51 ppm), Th (2.9 ± 0.47 ppm) and K 2 O (4.32 ± 0.26 %) contents determined in the laboratory by gamma-ray spectrometry from representative samples are in good accordance with fast in situ measurements carried out with the same technique and also with conventional chemical analysis. Estimated activities for K-40, Ra-226 and Th-232 were, on average, 1022 ± 36 Bq kg −1 , 84 ± 9 Bq kg −1 and 6.8 ± 1.6 Bq kg −1 . On the basis of these results, the
doi:10.5194/nhess-12-395-2012 fatcat:t5f5yduuqner7kfitkangamh5e