Isochrone fitting of the observed ⁷Li-abundance data. The model that gives the best CMD fit in Fig. 8 is compared to the 3D+NLTE-corrected data from Lind et al. (2009). Models with (Λ_e = 0.6, α_th = 100), (Λ_e = 0.14, α_th = 100), and one with (Λ_e = 0.05, α_th = 50) are also plotted here for the sake of comparison. The insert panel zooms in on the onset of thermohaline mixing. The colour bar indicates the observed masses (Masses are derived from g, T_eff, and L values provided by Lind et al. 2009.).