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tokens: as a function of metallicity and the data (see e.g. fig. 10 of Nomoto et al. 2013 ). Regardless of this fact, we can empirically compare the derived values of [V/Fe] for our stars with those from known populations. Fig. 3 shows the derived values of [V/Fe] as a function of metallicity for the extreme-velocity stars (black) compared to the Galactic disc (light green circles Battistini Bensby 2016 ), the Galactic halo (Yong et al. 2013 ; Roederer et al. 2014 ), and the LMC (Van der Swaelmen et al. 2013 ). The candidate extreme-velocity stars have a wide range in [V/Fe], again consistent with the large scatter observed for the Galactic halo. Cu : Copper (Cu) is an odd-Z element that is thought to be largely produced via SNIa and hypernovae but is also produced by secondary phenomena in massive stars and the weak s-process (e.g. Mishenina et al. 2002 ). Like many elements, the exact nucleosynthetic process that forms Cu is still under debate (e.g. Andrievsky et al. 2018 ). As shown in Fig. 4 , previous surveys found a large scatter in [Cu/Fe] at the metallicities of our stars, and similar low values in the LMC and stellar halo. Again, the stars in our sample fit within the scatter of the stellar halo, but Cu does not allow us to distinguish between stars born in the Galactic disc, halo or LMC. Figure 4. The [X/Fe] ratios of the program stars (black filled symbols) as a function of [Fe/H] for Cr, Mn, Ni, and Zn from top to bottom, respectively, on the left and Sc, Co, and Cu from top to bottom, respectively, on the right. These largely represent the Fe-peak elements. The symbols are the same as in Fig. 3 . Sc : Scandium (Sc) is an odd-Z element that, similarly to vanadium, has a poorly understood nucleosynthesis production mechanisms. This is evident by the large discrepancies between the theoretically computed and observed trends of [Sc/Fe] as a function of [Fe/H] (e.g. Kobayashi et al. 2006 ; Nomoto et al. 2013 ). As seen in Fig. 4 stars belonging to either the LMC or Galactic disc show [Sc/Fe] increasing with decreasing metallicity, with [Sc/Fe] lower in the LMC at fixed metallicity compared to the Galactic disc (Van der Swaelmen et al. 2013 ). On the other hand, stars in the Galactic halo have [Sc/Fe] values which are either slightly enhanced (Yong et al. 2013 ) or solar (Roederer et al. 2014 ) though with large intrinsic scatter. The candidate extreme-velocity stars are all enhanced in [Sc/Fe] at levels consistent with the Galactic halo but not with the LMC. 4.4 Fe-peak elements: Cr, Mn, Co, Ni, Zn Unlike the α or odd-Z elements, the Fe-peak elements, such as chromium (Cr), scandium (Sc), manganese (Mn), cobalt (Co), nickle (Ni), and zinc (Zn), are formed through a variety of paths (Iwamoto et al. 1999 ; Kobayashi et al. 2006 ) but are largely dispersed into the ISM in a similar way as iron. As such, these Fe-peak elements largely track the abundance of Fe. At the metallicity range of the candidate extreme-velocity stars (–2 [Fe/H] –1),