Fig. 12

Precision of Pb isotope analyses of angrites and reference material SRM 981 measured on the GSC Triton from Amelin and Davis (2006), Amelin (2008a, b), and Amelin et al. (2024), compared to theoretical noise level calculated as shown in Figs. 10 and 11 (baseline noise equal to Johnson–Nyquist of 10¹¹ Ohm resistors, ion yield 4%, baseline integration time 30 min, signal measurement time either 10 min or 60 min, data acquisition occupies 80% of the total measurement time). The horizontal orange line shows the significance threshold