TMA=1/lambda ln (((187Os/188Os)sample-(187Os/188Os)chond) / ((187Re/188Os)sample-(187Re/188Os)chond]+1). TRD=(minimum) time of rhenium depletion calculated using a mean present-day chondritic value 187Os/188Os=0.1278 from Walker et al. (2002, doi:10.1016/S0016-7037(02)01003-7) and assumes that 187Re/188Ossample=0. Mean total procedural blanks (10 total) were 3.85 +/- 3.0 pg/g for Re and 1.85 +/- 2.15 pg/g, for Os with a 187Os/188Os=0.170 +/- 0.131 resulting in maximum blank corrections of 17.6% and 0.24% for Re and Os respectively. Given isotope ratios blank corrected. 187Os/188Os ratios normalised to 192Os/188Os=3.08271 and corrected using measured 18O/16O and 17O/16O of 0.002047 and 0.00037 respectively. Johnson Matthey (n=26) 2.75 ng Os standard 187Os/188Os=0.17373 +/- 12 (2sigma)