Tin rich layers on ancient copper based objects

A number of archaeological copper based objects, presenting tin rich layers on the surface, dated to different periods and coming from very different geographical contexts in the Ancient World, are discussed in this paper. The different reasons for the presence of tin rich layers on the surface of ancient items have been discussed before. However, new analyses of archaeological objects now offer data on the early use of tinning, on the use of high tin alloys for distinctive objects in the Bronze Age and of the use of special surface treatments employed in antiquity, which might give new insights into the early history of metallurgy and new elements for the identification of trade routes. A surface treatment, possibly employed in Roman times, is also discussed.