[α/Fe] vs [Fe/H] relation for the spheroidal bulge (top-left), the inner-thick disc (top-middle), the bar (top-right), the X₄ orbit family of stars (bottom-left), and the non-confined stars with (−0.4 < L_zi < 0.4) (bottom-right). Each panel shows the KDE - overlaid with contours highlighting regions of high stellar density. Colours indicate density levels, with red being the highest, followed by blue and green, while white indicates regions with no stars. The [α/Fe] vs [Fe/H] plane is further divided into rectangular regions with lines at [Fe/H]=[−1.0,−0.5,0.0] and [α/Fe]=[0.0,0.1,0.2]. The fraction of stars in each region is provided.