Neodymium isotope ratios are measured as metal ions in a Re triple filament assembly in a three sequence dynamic routine utilizing seven Faraday cups. By maintaining a 3V 144Nd beam for 150 cycles, an internal precision of 3 ppm (1-sigma) on the 143Nd/144Nd ratio is consistently achieved with an exponential law correction relative to 146Nd/144Nd = 0.7219. External reproducibility of the JNdi-1 Nd isotopic standard since installation has been maintained at 0.5121035 ± 11 (2.2 ppm, 1-sigma, n=28; literature value ~ 0.512110).
We are capable of measuring the Nd isotopic compositions of a variety of rocks, minerals, fossil material, waters and soils. We also have a carefully calibrated, highly enriched, mixed 149Sm-150Nd spike for isotope dilution measurement of 147Sm/144Nd, suitable for total spiking of most samples.