Here, the grave of a well established man of distinction and a ritual store, dating from the 9th century AD, contained both chased copper objects and elaborate castings of leaded bronze.
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Smelting and melting of copper and it alloys such as leaded bronze were smelted in crucibles similar to those of the roman period which have thinner walls and flat bases to sit within the furnaces.
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Three sites have been excavated, revealing hundreds of ritual vessels and regalia castings of bronze or leaded bronze that are among the most inventive and technically accomplished bronzes ever made.
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The Igbo-Ukwu artefacts were made between the 9th and 11th centuries AD of tin-bronze and leaded tin-bronze, and so required the metals copper, lead and tin.