Low-metallicity stars are witnesses of the first stellar nucleosynthesis events in the Galaxy, as their surface abundances reflect the composition of the interstellar medium from which they were born. Aside from the primordial Big Bang nucleosynthesis, massive stars, due to their short lifetimes, dominate the wind and explosive ejecta into the interstellar medium of the early Galaxy. Most of them will end as core-collapse supernova (CCSN) explosions, and typical abundance patterns reflect their influence. Essentially all CCSNe eject Fe (decaying from radioactive 56Ni). Therefore, it is interesting to test whether other elements found in low-metallicity stars are correlated with Fe, i.e. whether they have been co-produced in the contributing sources or require either different or additional astrophysical origins. We concentrate in our analysis on stars with [Fe/H]<-2, i.e. evolutionary phases of the Galaxy before low and intermediate mass stars (or type Ia supernovae) could contribute, and when only one or very few events had the chance to have their ejecta incorporated in newly forming stars. Following our recent investigations into the origin of r-process elements (Farouqi et al., 2022), we extended the present study to examine Pearson and Spearman correlations of Fe with Li, Be, C, N, Na, Mg, Si, S, Ca, Ti, Cr, Ni, Zn, Ge, Se, Sr, Zr, Ba, Ce, Sm, Eu, Yb, Lu, Hf, Os, Ir, Pb, Th, and U, obtaining important clues on their origin, including a variety of core-collapse supernovae