Colour magnitude diagrams of ED groups. The stars for which we measure chemical abundances are shown as larger markers with different symbols. The last panel shows a randomly selected 1% sample of GE stars and those for which we measure chemical abundances are shown with larger markers. In all cases, the colours and magnitudes have been corrected for extinction using the Lallement et al. (2022) dust maps. Horizontal branch stars have been removed from the isochrone fitting of the ED groups, indicated by the grey dashed line. Stars with high extinction A_G > 0.7 or that are fainter than M_G = 4.5 are also removed from the isochrone fitting. All of these stars not included in the isochrone fitting are shown as white symbols. The compatible BaSTi IAC alpha-enhanced isochrones for each of the ED groups are shown and the range of age and [Fe/H] that these isochrones span are given in the legend. The colour-magnitude shift (Δ_c, Δ_m) of (−0.035, 0.04) from Gallart et al. (2024) has been applied to the isochrones for fitting and plotting. The background shows a density plot of the local halo stars.