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Analysis of early copper‐base artifacts invariably reveals traces of iron. Iron enters the copper during the smelting process and the level of iron in the metalwork is an indication of the smelting technology. In areas such as Western Europe where prehistoric slag heaps are absent even in the proximity of undoubted ancient mines, the iron content is low reinforcing the link between smelting technology and iron content. Very occasionally the iron content was deliberately encouraged and alloys containing between 30% and 50% of iron in copper were made, mainly for use in currency. These alloys are without modern parallel and their metallography and method of production are considered in some detail here.

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Elevated concentrations of P2O5 of 2–12 wt% absolute were observed in the matrices of a small group of ceramics with the electron microprobe. P2O5, CaO and FeOt are enriched towards the surfaces in some cases and elemental correlations suggest precipitation of a crystalline calcium phosphate with a stoichiometry close to CaO · P2O5. Scanning electron microscopy with X‐ray mapping showed P2O5 to be dispersed in the ceramic matrix on a very fine scale, while X‐ray diffraction detected no crystalline phosphate. Parallels are drawn with the precipitation of phosphate in the surfaces of weathered glass. It is concluded that the amorphous phases produced on firing behave as chemically active substrates which facilitate the adsorption or precipitation of very fine grained calcium phosphate from the burial environment.

Tin‐rich surfaces found on bronze antiquities may be the result of man‐made or natural processes. The difficulties encountered in distinguishing between these processes are discussed and illustrated with reference to the surface structures obtained on experimentally tinned copper and bronze. Heat treatments were carried out on the experimental material to allow observation of the growth of the intermetallic compound layers on the surface, and of changes that occur at various significant temperatures. The experimental reduction of cassiterite directly onto the surface of copper and bronze is illustrated for the first time. Examples of tin‐rich surfaces found on various antiquities are illustrated and are compared with the experimental material for interpretation. Scanning electron microscopy and microanalysis were the primary tools used in this study.