Table 1: Instrumental settings and calibration for ICP-MS.

ICP-MS instrument
 Forward power1300 W
 Sampler and skimmer conesNickel
 Argon flow rates
  Cool gas 14.5 L min−1
  Auxiliary 0.76 L min−1
  Nebuliser 0.92 L min−1
Acquisition parameters
 Ion monitoring mode
  Number of sweeps 60
  Channels per mass 1
  Dwell time 10 ms
  Number of main runs 3
 Survey mode
  Cannels per mass 10
  Sweeps 10
  Dwell time 0.6 ms
Internal standards 6Li, 45Sc, 115In, 159Tb, 209Bi