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After the chemical analysis of the commemorative heads, the relief plaques and the statuettes from Benin in the Ethnological Museum in Berlin remaining smaller objects, the pendants, bracelets, bells and various tools, vessels and instruments have been analyzed by means of an atomic absorption analysis. Since from earlier analyses a relation between the composition and the type of Benin objects became obvious, again this study should first of all reveal the type of alloys which had been used for the manufacture of this group of objects. As a result of the analysis of the elements copper, tin, lead and zinc, which are the main elements of copper alloys, it has been found that brasses with very high concentrations of zinc predominate. These zinc rich brasses came in use in Benin not earlier than in the 19th century, when techniques had been developed to produce this type of brass. Besides this large group of late objects made from a brass rich in zinc, there are objects with medium and low concentrations of zinc and also tin bronzes which are free from zinc. By means of the trace element analysis, first of all from the concentrations of nickel, antimony, arsenic, silver and cadmium it could be shown, that most of these objects, which occur also in the early period of the Benin kingdom, are quite recent, since, contrary to the early objects with high concentrations of these trace elements, their low concentrations of trace elements prove, that they have been made in the 19th century. [ABSTRACT FROM AUTHOR]

A series of 56 brass statuettes from Benin has been analysed by emission spectrography and atomic absorption spectrometry. Since from already published analyses of memorial heads and relief plates it is obvious that there is clear relation between the composition of a brass object from Benin and its date of manufacture, there was a considerable interest to check whether the alloys used for the statuettes fit into this already established system. The metal analysis of the statuettes showed that most of them have been made from a brass with very high amounts of zinc, which is a feature of products of the later phases of manufacture. But there are too some statuettes made of bronze or of a brass with low concentrations of zinc, characteristic for early objects. Besides the high concentration of zinc there are further arguments of a late production, like the high concentration of cadmium or the decrease of trace element concentrations, first of all of nickel and antimony. With respect to characteristic features of defined groups of statuettes, altar groups are rich in zinc, while statuettes of dignitaries contain less zinc. Among the statuettes of animals, those rich in zinc are frequent, but always there are a few examples with low concentrations of zinc, indicating an earlier origin. [ABSTRACT FROM AUTHOR]

From the Ethnological Museum of Berlin I98 relief plates have been analyzed by atomic absorption spectroscopy. It has been found, that they have been made from brass, which is in its composition entirely different from the brass which had been used for commemorative heads, but identical in their composition with that of Udo heads. The characteristic feature of the brass of the relief plates is an elevated amount of lead, while commemorative heads normally are relatively poor in lead. Further. it became obvious that relief plates with animals and Europeans usually are poorer in zinc and lead than most of the relief plates with Africans. The supposition of Sydow (1932) that flat plates are earlier than those plates with a marked relief is supported, since an increase of zinc is a sign for a later production. A considerable number of relief plates could be found which have an identical composition, due to a joint production from one batch of brass. This leads to a determination of the sequence of brass cargos brought from Europe to Benin. [ABSTRACT FROM AUTHOR]