Isotope dilution concentration determinations are accurate to approx. 1% for Rb and Sr, and 0.5% for Sm and Nd. Total procedural blanks averaged apporx. 1 ng for Sr and 100 pg for Nd, during the study
Samples were digested in 50% HCl at 95°C for about 45 minutes. The insoluble fraction was filtered off and the residue was ignited for 15 minutes at 1000°C. From 1983 until 1989 NOAA-NCEI compiled the
