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We report on the structural and chemical composition of copper and tin ingots from the Late Bronze Age shipwreck of Kas/Uluburun, found at the southern coast of Anatolia. The ship carried ten tons of copper and one ton of tin. The cargo thus represents the "world market" bulk metal in the Mediterranean. It is the aim of this paper to evaluate the quality of metal traded during this period and to discuss the making of these ingots. Cores drilled from a number of ingots show an extraordinary high porosity of the copper. Inclusions of slag, cuprite, and copper sulfides suggest that the ingots were produced from raw copper smelted in a furnace and, in a second step, remelted in a crucible. Internal cooling rims point to multiple pouring. We doubt that the entity of an ingot was made from one batch of metal tapped from a Late Bronze Age smelting furnace. The quality of the copper is poor and needed further purification before casting, even if the chemical composition shows that it is rather pure. The copper was not refined. The tin ingots in most cases are heavily corroded. The metal is low in trace elements except for lead.