Lead

Like the arsenic, the lead in all the Kish copper-based artifacts in this study most likely derive from the original copper ore, its variation (from near-trace levels to around 1.3%) simply reflecting differences in the conditions of smelting of the original copper ore (Tylecote et al. 1977). 

ED I: 
Range: <0.018%–0.41% (n=13) 
Mean: 0.17% ± 0.04% (1 standard error) 
Highest Pb-level: Bident (inv. V 793/794)

ED III/Akk: 
Range: <0.026%–1.3% (n=43) 
Mean: 0.25% ± 0.04% (1 standard error) 
Highest Ni-level: Awl/chisel (inv. FM228 719)