Determination of metallicity and microturbulence of stars of Precision sample II. The abundances of Fe I lines are represented by cross symbols, whereas those of Fe II are represented by red circles. Regressions of each species are represented by the black dotted and red dotted lines, respectively. The red line represents the regression of both Fe I and Fe II species together. The shade represents 1σ dispersion. Regressions are computed considering 2σ clipping.