Observed abundance trends with evolutionary stage of lithium. Green crosses indicate individual stellar abundances, while bullets represents the abundance derived from the co-added spectra within each group as a function of T_eff. Solid lines represent predictions from stellar evolution models including AD and AddMix with two different efficiencies, at 13.5 Gyr. The blue curve represents high-efficiency mixing (T₀ = 6.20) while the red curve corresponds to low-efficiency mixing (T₀ = 6.00). The dashed line gives the original Li abundance for the mean of our two highest detected Li abundances following the AD model with AddMix parameterised by T₀ = 6.20, log ε(Li) = 2.58 ± 0.1. The dotted line with the olive-brown shaded area shows the predicted primordial lithium abundance (“CMD+BBN”: log ε(Li) = 2.71 ± 0.06; Cyburt et al. 2010). The purple shaded area represent the overlapping 1-σ uncertainties between the two values. (This figure is available in colour in electronic form.)