Comparison between the spectra of NGC1786-978 (left panels) and NGC1786-2310 (right panels) around the Mg line at 5711 Å (upper panels) and the K line at 7699 Å (lower panels). The solid black lines represent the observed spectra, the solid red lines the best-fit synthetic spectra, and the dash-dotted blue lines the synthetic spectra with the abundances varied by ±0.2 dex with respect to the best values. In the bottom-right corners are the names of the stars and the corresponding [Mg/Fe] and [K/Fe] abundance ratios.