Natural radioactivity of rocks from the historic Jeroným Mine in the Czech Republic

Abstract This study reports the natural radioactivity of characteristic rocks found in historic Jeroným Mine Czech Republic as measured under laboratory conditions. The analyzed included granites and schists weathered to varying degrees collected from different levels underground workings Mine. mine itself has been subject metal extraction (mainly tin tungsten) since sixteenth century recently developed a cultural scientific attraction open public. Activity concentrations 40 K, 232 Th 238 U were nine rock samples using gamma-ray spectrometry. activity K varied 595 Bq kg −1 1244 , while 25 55 . activities associated with ranged 46 386 used estimate two radiation hazard indices typically applied building materials, concentration index I external H ex Mean respective values 1.02 0.77 for indicate that meet radiological safety standards materials do not pose risk potential tourists staff.