Optical emission spectrographic analysis was used for the major constitutents of 57 Cu alloy samples from the Benin Museum; the Tada collection; and excavations of the site of Igbo Jonah at IgboUkuru in eastern Nigeria. The results show that earlier opinions that brass may have been early and bronze late in this region are not confirmed. A correlation matrix for Cu, Sn, Pb and Zn in 29 samples was prepd. 38 references. -- AATA