The isotopes97Ru,103Ru and105Ru, produced by reactor irradiation of elemental ruthenium, were applied as triple comparators in the activation analysis
of rock FU-41, a basanitoid from Fuerteventura, Canary Island. The concentrations of the following elements were determined:
Sm, Sc, Fe, Co, Na, La, Hf, Eu, Th and Cr. The aim of this work was the experimental control of the error theory of the multiple
comparator method as well as the experimental check of the accuracy.