Gas Fe abundance as a function of stellar over baryon fraction. The shaded gray region represents the Fe abundance measurements for massive clusters. The red shaded region shows where f_⋆/f_b values for massive systems, as reported by Shuntov et al. (2022), are consistent with Fe abundance measurements. The shaded blue region shows how constraints on $r_o{\mathcal{Y}}_{\mathrm{Fe},\odot }-Z_{\mathrm{Fe},\odot }^{\star }$ allow us to estimate Fe abundance for ∼10¹² M_⊙ halos from the value of the peak stellar fraction, as measured by Shuntov et al. (2022).