Maximum amplitude of refractory-element depletions. Crosses are the relative abundance ratios of the most refractory-element-depleted stars in our samples, using the pristine stars as reference for the Δ [X/Fe] values. Filled circles with error bars represent the weighted mean and standard deviation of the data plotted with crosses. Thus, they illustrate the amplitude of refractory-element depletions. The top (bottom) panel corresponds to the warm (metal-rich) sample.