Spectral section from 5495−5535 A of three stars with [Fe/H] near −2 (green), −1.5 (blue), and −1.0 (purple). Line features for Fe I, Ti I, Ca II, Sc II, and Mg I are labeled. Fluxes are normalized, with the [Fe/H] ≈ −1.5 spectrum offset by 0.5
and the [Fe/H] ≈ −2 spectrum offset by 1.