The present invention relates to a method for associating information with a n article (fig. 1), an isotopic labeling composition to label an article (15) with information using at least two different isotopes of an element, and an article labeled with the labeling composition. In the labeling composition, the isotopes of the labeling composition have an abundance ratio that is detectably different from the natural abundance ratio thereof. By detecting the abundance ratio(s) of the isotopes in the labeling composition, via lase r ablation/magnetic spectroscopy, an NQR spectrometer (40), an NMR spectromete r (10), an IR spectrometer, or a microwave spectrometer, information about the article can be determined. The invention may be used to identify, authentica te or determine the source or origin of an article or to provide detailed information about an article.
USE OF ISOTOPES TO PROVIDE INFORMATION TO AN ARTICLE