A reconsideration of the Iberian background to Beaker metallurgy
With the recognition of only four metals we can gain a clearer appreciation of the technology of copper working around the Tagus estuary. The main technical innovation was the appearance of tin bronze alloys of Atlantic and Agraric traditions. But prior to this, no major technological discontinuity between the VNSP and Beaker cultures can be identified on the basis of the more than 400 SAM analyses. We can see the same 2% arsenical alloy in use in VNSP times to manufacture awls, flat axes and chisels as in the Beaker period for the production of Palmela Points. Even tin bronze is represented in both cultures, as shown by the VNSP chisel and a few rare Palmela Points. All the techniques used in Beaker metal manufacturing were already known to the VNSP smiths: cold hammering (on the flat axes), arsenical and tin bronze alloys were in use; even the same metal (presumably from the same ore sources) was used. Whatever we may believe about the typological development of certain artefacts, the apparent continuity of metallurgical knowledge and skills strongly suggests that Beaker metallurgy is merely a slightly more developed from of VNSP metallurgy, continuing on as before but with an increasing preference for the arsenic alloys. The increasingly deliberate control in ore selection or alloying was accompanied by more extensive and refined cold working to take full advantages of the properties of the arsenical inclusions. Thus a gradualpreference for consistent production of arsenical alloys developed at the same time as Beaker pottery became popular.
The absence of carbon-14 dates hinders an accurate estimate of the time-depth involved in the pre-Atlantic traditions, but a guess-date of 2,500-1,500 B.C. ought to convey the right order of magnitude.
The continuity of metal-working and settlement and burial patterns aroun dthe Tagus contrasts with S.E. Spain where no such pattern can be distinguished. Only around the Tagus estuary can Beaker metallurgy have any real background,a nd it would not be hard to see comb-decorated Beakers as the last phase of the VNSP culture.