Ca II index plotted vs. the Hδ/Fe I λ4045 index for stars in the CFSL. Different symbols denote stars in various gravity and metallicity bins. Large filled circles are for stars with intermediate gravity of 3.3 < log g ≤ 3.7. Large octagonal asterisks are for low‐gravity (supergiant) stars with 1.8 ≥ log g. Giant stars (1.8 < log g ≤ 3.3) are plotted as large open symbols, with triangles, squares, circles, and pentagons referring, respectively, to the following metallicity intervals: [Fe/H] > +0.3; +0.3 ≥ [Fe/H] > −0.4; −0.4 ≥ [Fe/H] > −1.5; −1.5 ≥ [Fe/H]. Dwarfs are plotted as small symbols, with the following scheme: filled squares for [Fe/H] > +0.3; times crosses for +0.3 ≥ [Fe/H] > −0.2; open squares for −0.2 ≥ [Fe/H] > −0.75; open triangles for −0.75 ≥ [Fe/H] > −1.25; filled triangles for −1.25 ≥ [Fe/H].