The measurement of the isotopic ratios of some elements, supplemented by historical and archaeological considerations, can provide information on the geographic origin. The activity of LNGS inherent in cultural heritage consists in the measurement of isotopic ratios (mainly Pb and Sr) in paintings, metallic and biological finds. Extremely accurate and precise measurements are obtained by mass spectrometry with thermal ionisation source (TIMS). Additional information is obtained from the elemental characterization by ICP-MS analysis.