Pb isotope analyses were corrected for mass fractionation using measured values of NBS981 and amounted to 0.12+/-0.02 (1 S.D.) %/AMU. The strontium isotope analyses were corrected for Rb interference, the ratios normalised to 86Sr/88Sr=0.1194 and corrected for fractionation by the exponential law and the results monitored by the international standard NBS987: 87Sr/86Sr=0.710257+/-0.000008 (1 S.D.), N=16. Neodymium was corrected for interference of Sm and fractionation by normalizing to 146Nd/144Nd=0.7219. Laboratory standard JM Nd yielded: 143Nd/144Nd=0.511123+/-0.000016 (1 S.D.), N=10, in the period of measurement. Within run precision was always insignificant compared to reproducibility of the reference materials.