2 5 4 1 ( 0 1 ) 0 0 4 2 0 - X 100 T. Waight et al. / Chemical Geology 186 (2002) 99–116 Rb – Sr ratio...Blichert-Toft et al., 1997; Halliday et al., 1998; Yi et al., 1998; Stirling et al., 2000), particularly...1993; White et al., 2000), Fe (using Cu) (Anbar et al., 2000) and Cu and Zn (Maréchal et al., 1999; Zhu...Zhu et al., 2000). Halliday et al. (1998) suggested that Rb could be corrected for mass bias by measuring...MC-ICPMS, described in a companion paper (Waight et al., in preparation). The similar ionisation efficiencies |