Radioactive elements pigments

However, minute amounts of radium-226 remain. Because the radioactive elements that would be needed to make the polonimn-210 are mostly removed, the amormt of polonimn-210 decreases as the pigment ages. The ratio between the amoimts of the radium-226 and the polonium-210 is used to establish the age of paintings. A low ratio of radium to polonium indicates a recent painting. 

Natural element of rock, pigments, and dyes Natural element of rock, plating industry Natural radioactive element Tobacco products... 

Neutron activation analysis (NAA), based on the interaction of the object material with fast neutrons, has been used in the identification and determination of the content of elements present in pigments, coins and alloys, stone, glass, and pottery [26]. Multi-elemental analysis (about 20 elements) can be performed on small samples off less than 5 mg, with sensitivities in the ppm range. The requirement of a nuclear reactor, the handling of radioactive materials, and the time-consuming procedures required for preparing the samples are the main drawbacks of this technique. 

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