Igbo-Ukwu bronze "Roped Pot" and related finds documented by archaeology

The Igbo-Ukwu bronzes — including the celebrated roped pot and altar stands decorated with conventionalised spiders — were analysed and shown to be leaded bronze and near-pure copper, indicating sophisticated indigenous metallurgy using imported raw materials, with the lost-wax technique probably learned via trans-Saharan trade. (The site was excavated and published in the 20th century; the objects themselves date to the 9th century.)