Kiel diagram indicating the location of our sample stars and the corresponding errors. The solid lines denote PARSEC isochrones (Bressan et al. 2012) for solar metallicity ([Z] = 0.019 dex) and different ages from log t = 7.0 to 9.25, as indicated. The dotted lines give the positions for different masses of M_⊙ = 1.5, 2, 3, and 4, respectively. The seven stars that have not been found to exhibit chemical peculiarities in this study are indicated by open symbols in the upper panel. Lower panel: a zoomed-in version that includes information on the spectroscopic classifications, as indicated in the legend. We note that for the CP4 star KIC 4136285, no parameters are available in the Mathur et al. (2017) catalogue and the star is therefore missing in the diagram.