Distribution of GMM-classified stars in the APOGEE–Gaia and GALAH–Gaia samples in chemical dimensions ([Ni/Fe], [Eu/Mg]) that are not used in the GMM. Since [Ni/Fe] and [Eu/Mg] are not used in the GMM, the GMM result does not contain the modeled mean, covariance, and σ for these dimensions. Instead, we use the GMM classified member stars for each component and fit a Gaussian representing their distribution in each projection. This fit is marked with a dashed line. The color schema follows Figures 2 and 3. (a) [Ni/Fe] vs. [Fe/H] for the APOGEE–Gaia sample; (b) [Eu/Mg] vs. [Fe/H] for the GALAH–Gaia sample; (c) [Mg/Cu] vs. [Na/Fe] for the GALAH–Gaia sample.