  We investigate the impact of hyperfine splitting on stellar abundance
analyses of Mn and Sc, and find that incorrect hfs treatment can lead to
spurious abundance trends with metallicity. We estimate corrections to a recent
study by Nissen et al. (2000), and find: (1) [Mn/Fe] is described by a bimodal
distribution, with [Mn/Fe] ~ -0.3 for stars [Fe/H] < -0.7, and [Mn/Fe] ~ -0.05
for stars at higher metallicity, suggestive of a transition between halo/thick
disk and thin disk populations. (2) The large majority of stars show nearly
solar [Sc/Fe] ratios; although important deviations cannot be ruled-out.
